I was with Buraida on a cloudy day and he said, "Offer the `Asr prayer earlier as the Prophet said, 'Whoever leaves the `Asr prayer will have all his (good) deeds annulled." (See Hadith No. 527 and 528)

The Prophet said, "On the Day of Resurrection the Believers will assemble and say, 'Let us ask somebody to intercede for us with our Lord.' So they will go to Adam and say, 'You are the father of all the people, and Allah created you with His Own Hands, and ordered the angels to prostrate to you, and taught you the names of all things; so please intercede for us with your Lord, so that He may relieve us from this place of ours.' Adam will say, 'I am not fit for this (i.e. intercession for you).' Then Adam will remember his sin and feel ashamed thereof. He will say, 'Go to Noah, for he was the first Apostle, Allah sent to the inhabitants of the earth.' They will go to him and Noah will say, 'I am not fit for this undertaking.' He will remember his appeal to his Lord to do what he had no knowledge of, then he will feel ashamed thereof and will say, 'Go to the Khalil--r-Rahman (i.e. Abraham).' They will go to him and he will say, 'I am not fit for this undertaking. Go to Moses, the slave to whom Allah spoke (directly) and gave him the Torah .' So they will go to him and he will say, 'I am not fit for this undertaking.' and he will mention (his) killing a person who was not a killer, and so he will feel ashamed thereof before his Lord, and he will say, 'Go to Jesus, Allah's Slave, His Apostle and Allah's Word and a Spirit coming from Him. Jesus will say, 'I am not fit for this undertaking, go to Muhammad the Slave of Allah whose past and future sins were forgiven by Allah.' So they will come to me and I will proceed till I will ask my Lord's Permission and I will be given permission. When I see my Lord, I will fall down in Prostration and He will let me remain in that state as long as He wishes and then I will be addressed.' (Muhammad!) Raise your head. Ask, and your request will be granted; say, and your saying will be listened to; intercede, and your intercession will be accepted.' I will raise my head and praise Allah with a saying (i.e. invocation) He will teach me, and then I will intercede. He will fix a limit for me (to intercede for) whom I will admit into Paradise. Then I will come back again to Allah, and when I see my Lord, the same thing will happen to me. And then I will intercede and Allah will fix a limit for me to intercede whom I will let into Paradise, then I will come back for the third time; and then I will come back for the fourth time, and will say, 'None remains in Hell but those whom the Qur'an has imprisoned (in Hell) and who have been destined to an eternal stay in Hell.' " (The compiler) Abu `Abdullah said: 'But those whom the Qur'an has imprisoned in Hell,' refers to the Statement of Allah: "They will dwell therein forever." (16.29)

Abdullah ibn Zalim al-Mazini said: I heard Sa'id ibn Zayd ibn Amr ibn Nufayl say: When so and so came to Kufah, and made so and so stand to address the people, Sa'id ibn Zayd caught hold of my hand and said: Are you seeing this tyrant? I bear witness to the nine people that they will go to Paradise. If I testify to the tenth too, I shall not be sinful.

I asked: Who are the nine? He said: The Messenger of Allah (saws) said when he was on Hira': Be still, Hira', for only a Prophet, or an ever-truthful, or a martyr is on you. I asked: Who are those nine? He said: The Messenger of Allah, AbuBakr, Umar, Uthman, Ali, Talhah, az-Zubayr, Sa'd ibn AbuWaqqas and AbdurRahman ibn Awf. I asked: Who is the tenth? He paused a moment and said: it is I.

Abu Dawud said: This tradition has been transmitted by al-Ashja'i, from Sufyan, from Mansur, from Hilal b. Yasaf, from Ibn Hayyan on the authority of 'Abd Allah b. Zalim through his different chain of narrators in a a similar manner.

The Messenger of Allah (saws) said: The best day on which the sun has risen is Friday; on it Adam was created, on it he was expelled (from Paradise), on it his contrition was accepted, on it he died, and on it the Last Hour will take place. On Friday every beast is on the lookout from dawn to sunrise in fear of the Last Hour, but not jinn and men, and it contains a time at which no Muslim prays and asks anything from Allah but He will give it to him. Ka'b said: That is one day every year. So I said: It is on every Friday. Ka'b read the Torah and said: The Messenger of Allah (saws) has spoken the truth. AbuHurayrah said: I met Abdullah ibn Salam and told him of my meeting with Ka'b. Abdullah ibn Salam said: I know what time it is. AbuHurayrah said: I asked him to tell me about it. Abdullah ibn Salam said: It is at the very end of Friday. I asked: How can it be when the Messenger of Allah (saws) has said: "No Muslim finds it while he is praying...." and this is the moment when no prayer is offered. Abdullah ibn Salam said: Has the Messenger of Allah (saws) not said: "If anyone is seated waiting for the prayer, he is engaged in the prayer until he observes it." I said: Yes, it is so.

We were in Siffin and Sahl bin Hunaif got up and said, "O people! Blame yourselves! We were with the Prophet on the day of Hudaibiya, and if we had been called to fight, we would have fought. But `Umar bin Al Khatab came and said, 'O Allah's Apostle! Aren't we in the right and our opponents in the wrongs' Allah's Apostle said, 'Yes.' `Umar said, 'Aren't our killed persons in Paradise and their's in Hell?' He said, 'Yes.' `Umar said, 'Then why should we accept hard terms in matters concerning our religion? Shall we return before Allah judges between us and them?' Allah's Apostle said, 'O Ibn Al- Khattab! I am the Apostle of Allah and Allah will never degrade me. Then `Umar went to Abu Bakr and told him the same as he had told the Prophet. On that Abu Bakr said (to `Umar). 'He is the Apostle of Allah and Allah will never degrade him.' Then Surat-al-Fath (i.e. Victory) was revealed and Allah's Apostle recited it to the end in front of `Umar. On that `Umar asked, 'O Allah's Apostle! Was it (i.e. the Hudaibiya Treaty) a victory?' Allah's Apostle said, "Yes".

The Prophet , sent an army and appointed some man their commander The man made a fire and then said (to the soldiers), "Enter it." Some of them intended to enter it while some others said, 'We have run away from it (i.e., embraced Islam to save ourselves from the 'fire')." They mentioned that to the Prophet, and he said about people who had intended to enter the fire. ''If they had entered it, they would have remained In it till the Day of Resurrection.'' Then he said to others, "No obedience for evil deeds, obedience is required only in what is good ."

I heard Al-Bara' saying, "The above Verse was revealed regarding us, for the Ansar on returning from Hajj never entered their houses through the proper doors but from behind. One of the Ansar came and entered through the door and he was taunted for it. Therefore, the following was revealed: -- "It is not righteousness That you enter the houses from the back, But the righteous man is He who fears Allah, Obeys His order and keeps away from What He has forbidden So, enter houses through the proper doors." (2.189)

Yahya related to me from Malik, from Abdullah ibn Dinar, that Abdullah ibn Umar used to say, "Anyone that does umra in the months of hajj, that is, in Shawwal, Dhu'l-Qada, or in Dhu'l-Hijja before the hajj, and then stays in Makka until the time for hajj, is doing tamattu if he then does hajj. He must sacrifice whatever animal it is easy for him to obtain, and if he cannot find one then he must fast three days during hajj and seven days when he returns."

Malik said, "This is only the case if he stays until the hajj and does hajj in that same year."

Malik said that if someone who was from Makka but had stopped living there and gone to live elsewhere, came back to do umra in the months of the hajj and then stayed in Makka to begin hajj there, he was doing tamattu, and had to offer up a sacrificial animal, or fast if he could not find one. He was not the same as the people of Makka.

Malik was asked whether someone who was not from Makka and entered Makka to do umra in the months of hajj with the intention of staying on to begin his hajj there was doing tamattu or not, and he said, "Yes, he is doing tamattu, and he is not the same as the people of Makka, even if he has the intention of staying there. This is because he has entered Makka, and is not one of its people, and making a sacrifice or fasting is incumbent on anyone who is not from Makka, and, although he intends to stay, he does not know what possibilities might arise later. He is not one of the people of Makka."

Yahya related to me from Malik from Ishaq ibn Abdullah ibn Abi Talha that Anas ibn Malik said, "We would pray asr and anyone who then went to the Bani Amr ibn Awf would find them praying asr."

When the Messenger of Allah (saws) halted at a certain place (while on a journey), he would not leave that place till he offered the noon prayer. A man said to him: Even if in the middle of the day? He replied: Even if in the middle of the day.

While I was with Aisha, the mother of the Believers, a person from Iraq came and asked, "What type of shroud is the best?" `Aisha said, "May Allah be merciful to you! What does it matter?" He said, "O mother of the Believers! Show me (the copy of) your Qur'an," She said, "Why?" He said, "In order to compile and arrange the Qur'an according to it, for people recite it with its Suras not in proper order." `Aisha said, "What does it matter which part of it you read first? (Be informed) that the first thing that was revealed thereof was a Sura from Al-Mufassal, and in it was mentioned Paradise and the Fire. When the people embraced Islam, the Verses regarding legal and illegal things were revealed. If the first thing to be revealed was: 'Do not drink alcoholic drinks.' people would have said, 'We will never leave alcoholic drinks,' and if there had been revealed, 'Do not commit illegal sexual intercourse, 'they would have said, 'We will never give up illegal sexual intercourse.' While I was a young girl of playing age, the following Verse was revealed in Mecca to Muhammad: 'Nay! But the Hour is their appointed time (for their full recompense), and the Hour will be more grievous and more bitter.' (54.46) Sura Al-Baqara (The Cow) and Surat An-Nisa (The Women) were revealed while I was with him." Then `Aisha took out the copy of the Qur'an for the man and dictated to him the Verses of the Suras (in their proper order) .

The Prophet came out after the sun had declined and offered the Zuhr prayer (in congregation). After finishing it with Taslim, he stood on the pulpit and mentioned the Hour and mentioned there would happen great events before it. Then he said, "Whoever wants to ask me any question, may do so, for by Allah, you will not ask me about anything but I will inform you of its answer as long as I am at this place of mine." On this, the Ansar wept violently, and Allah's Apostle kept on saying, "Ask Me! " Then a man got up and asked, ''Where will my entrance be, O Allah's Apostle?" The Prophet said, "(You will go to) the Fire." Then `Abdullah bin Hudhaifa got up and asked, "Who is my father, O Allah's Apostle?" The Prophet replied, "Your father is Hudhaifa." The Prophet then kept on saying (angrily), "Ask me! Ask me!" `Umar then knelt on his knees and said, "We have accepted Allah as our Lord and Islam as our religion and Muhammad as an Apostle." Allah's Apostle became quiet when `Umar said that. Then Allah's Apostle said, "By Him in Whose Hand my life is, Paradise and Hell were displayed before me across this wall while I was praying, and I never saw such good and evil as I have seen today."

Yahya related to me from Malik from Thawr ibn Zayd ad-Dili from Abu'l-Ghayth Salim, the mawla of ibn Muti that Abu Hurayra said, "We went out with the Messenger of Allah, may Allah bless him and grant him peace, in the yearof Khaybar. We did not capture any gold or silver except for personal effects, clothes, and baggage. Rifaa ibn Zayd presented a black slave boy to the Messenger of Allah, may Allah bless him and grant him peace, whose name was Midam. The Messenger of Allah, may Allah bless him and grant him peace, made for Wadi'l-Qura, and when he arrived there, Midam was unsaddling the camel of the Messenger of Allah, may Allah bless him and grant him peace, when a stray arrow struck and killed him. The people said, 'Good luck to him! The Garden!' The Messenger of Allah said, 'No! By He in whose hand my self is! The cloak which he took from the spoils on the Day of Khaybar before they were distributed will blaze with fire on him.' When the people heard that, a man brought a sandal-strap or two sandal-straps to the Messenger of Allah, may Allah bless him and grant him peace. The Messenger of Allah, may Allah bless him and grant him peace, said, 'A sandal-strap or two sandal-straps of fire!' "

I came to `Aisha the wife of the Prophet during the solar eclipse. The people were standing and offering the prayer and she was also praying. I asked her, "What is wrong with the people?" She beckoned with her hand towards the sky and said, "Subhan Allah." I asked her, "Is there a sign?" She pointed out, "Yes." So I, too, stood for the prayer till I fell unconscious and later on I poured water on my head. After the prayer, Allah's Apostle praised and glorified Allah and said, "Just now I have seen something which I never saw before at this place of mine, including Paradise and Hell. I have been inspired (and have understood) that you will be put to trials in your graves and these trials will be like the trials of Ad-Dajjal, or nearly like it (the sub narrator is not sure of what Asma' said). Angels will come to every one of you and ask, 'What do you know about this man?' A believer will reply, 'He is Muhammad, Allah's Apostle , and he came to us with self-evident truth and guidance. So we accepted his teaching, believed and followed him.' Then the angels will say to him to sleep in peace as they have come to know that he was a believer. On the other hand a hypocrite or a doubtful person will reply, 'I do not know but heard the people saying something and so I said the same.' "

Allah's Apostle said, "Whoever could get one rak`a (of the Fajr prayer) before sunrise, he has got the (morning) prayer and whoever could get one rak`a of the `Asr prayer before sunset, he has got the (`Asr) prayer."

One day the Messenger of Allah (saws) entered the mosque. He saw there a man from the Ansar called AbuUmamah.

He said: What is the matter that I am seeing you sitting in the mosque when there is no time of prayer?

He said: I am entangled in cares and debts, Messenger of Allah.

He replied: Shall I not teach you words by which, when you say them, Allah will remove your care, and settle your debt?

He said: Why not, Messenger of Allah?

He said: Say in the morning and evening: "O Allah, I seek refuge in Thee from care and grief, I seek refuge in Thee from incapacity and slackness, I seek refuge in Thee from cowardice and niggardliness, and I seek in Thee from being overcome by debt and being put in subjection by men."

He said: When I did that Allah removed my care and settled my debt.

We entered upon Ibn `Abbas and he said "Are you not astonished at Ibn Az-Zubair's assuming the caliphate?" I said (to myself), "I will support him and speak of his good traits as I did not do even for Abu Bakr and `Umar though they were more entitled to receive al I good than he was." I said "He (i.e Ibn Az-Zubair) is the son of the aunt of the Prophet and the son of AzZubair, and the grandson of Abu Bakr and the son of Khadija's brother, and the son of `Aisha's sister." Nevertheless, he considers himself to be superior to me and does not want me to be one of his friends. So I said, "I never expected that he would refuse my offer to support him, and I don't think he intends to do me any good, therefore, if my cousins should inevitably be my rulers, it will be better for me to be ruled by them than by some others."

(While we were going for the Battle of Tabuk and when we reached the places of the dwellers of Al- Hijr), Allah's Apostle said about the dwellers of Al-Hijr (to us). "Do not enter (the dwelling places) of these people unless you enter weeping, but if you weep not, then do not enter upon them, lest you be afflicted with what they were afflicted with."

In the Pre-lslamic Period when the people assumed Ihram, they would enter their houses from the back. So Allah revealed:-- "And it is not righteousness that you enter houses from the back, but the righteous man is he who fears Allah, obeys His Orders and keeps away from what He has forbidden. So enter houses through their doors." (2.189)

`Umar came cursing the disbelievers (of Quraish) on the day of Al-Khandaq (the battle of Trench) and said, "I could not offer the `Asr prayer till the sun had set. Then we went to Buthan and he offered the (`Asr) prayer after sunset and then he offered the Maghrib prayer.

Yahya related to me from Malik from Nafi' that 'Abdullah ibn Umar used to do ghusl for ihram before he entered ihram, and for entering Makka, and for standing on the afternoon of 'Arafa.

My mother, Um Sulaim, took a Mudd of barley grain, ground it and made porridge from it, and pressed (over it), a butter skin she had with her. Then she sent me to the Prophet, and I reached him while he was sitting with his companions. I invited him, whereupon he said, "And those who are with me?' I returned and said, "He says, 'And those who are with me?" Abu Talha went out to him and said, "O Allah's Apostle! It is just a meal prepared by Um Sulaim." The Prophet entered and the food was brought to him. He said, "Let ten persons enter upon me." Those ten entered and ate their fill. Again he said, 'Let ten (more) enter upon me." Those ten entered and ate their fill. Then he said, "Let ten (more) enter upon me." He called forty persons in all Then Allah's Apostle ate and got up. I started looking (at the food) to see if it decreased or not.

Allah's Apostle used to like sweets and also used to like honey, and whenever he finished the `Asr prayer, he used to visit his wives and stay with them. Once he visited Hafsa and remained with her longer than the period he used to stay, so I enquired about it. It was said to me, "A woman from her tribe gave her a leather skin containing honey as a present, and she gave some of it to Allah's Apostle to drink." I said, "By Allah, we will play a trick on him." So I mentioned the story to Sauda (the wife of the Prophet) and said to her, "When he enters upon you, he will come near to you whereupon you should say to him, 'O Allah's Apostle! Have you eaten Maghafir?' He will say, 'No.' Then you say to him, 'What is this bad smell? ' And it would be very hard on Allah's Apostle that a bad smell should be found on his body. He will say, 'Hafsa has given me a drink of honey.' Then you should say to him, 'Its bees must have sucked from the Al-`Urfut (a foul smelling flower).' I too, will tell him the same. And you, O Saifya, say the same." So when the Prophet entered upon Sauda (the following happened). Sauda said, "By Him except Whom none has the right to be worshipped, I was about to say to him what you had told me to say while he was still at the gate because of fear from you. But when Allah 's Apostle came near to me, I said to him, 'O Allah's Apostle! Have you eaten Maghafir?' He replied, 'No.' I said, 'What about this smell?' He said, 'Hafsa has given me a drink of honey.' I said, 'Its bees must have sucked Al-`Urfut.' " When he entered upon me, I told him the same as that, and when he entered upon Safiya, she too told him the same. So when he visited Hafsa again, she said to him, "O Allah's Apostle! Shall I give you a drink of it (honey)?" He said, "I have no desire for it." Sauda said, Subhan Allah! We have deprived him of it (honey)." I said to her, "Be quiet!"

Yahya related to me from Malik from Abu'z-Zubayr al-Makki from Abu't-Tufayl Amir ibn Wathila that Muadh ibn Jabal told him that they went out with the Messenger of Allah, may Allah bless him and grant him peace, in the year of Tabuk, and the Messenger of Allah, may Allah bless him and grant him peace, joined dhuhr with asr and maghrib with isha. Muadh said, "One day he delayed the prayer, and then came out and prayed dhuhr and asr together. Then he said, 'Tomorrow you will come, insha' llah, to the spring of Tabuk. But you will not get there until well into the morning. No one who arrives should touch any of its water until I come.' We came to it and two men had got to it before us and the spring was dripping with a little water. The Messenger of Allah, may Allah bless him and grant him peace, asked them, 'Have you touched any of its water?' They said, 'Yes.' The Messenger of Allah, may Allah bless him and grant him peace, reviled them and said what Allah wished him to say. Then they took water with their hands from the spring little by little until it had been collected in something. Then the Messenger of Allah, may Allah bless him and grant him peace, washed his face and hands in it. Then he put it back into the spring and the spring flowed with an abundance of water and the people drew water from it. The Messenger of Allah, may Allah bless him and grant him peace, said, 'If you live long enough, Muadh, you will soon see this place filled with gardens.' "

I saw some agricultural equipment and said: "I heard the Prophet saying: "There is no house in which these equipment enters except that Allah will cause humiliation to enter it."

`Umar bin Al-Khattab came on the day of Al-Khandaq after the sun had set and he was abusing the infidels of Quraish saying, "O Allah's Apostle! I was unable to offer the (`Asr) prayer till the sun was about to set." The Prophet said, "By Allah, I have not offered this (i.e. `Asr) prayer." So we came down along with the Prophet to Buthan where he performed ablution for the prayer and then we performed the ablution for it. Then he offered the `Asr prayer after the sun had set, and after it he offered the Maghrib prayer.

I came to `Aisha while she was praying, and said to her, "What has happened to the people?" She pointed out towards the sky. (I looked towards the mosque), and saw the people offering the prayer. Aisha said, "Subhan Allah." I said to her, "Is there a sign?" She nodded with her head meaning, "Yes." I, too, then stood (for the prayer of eclipse) till I became (nearly) unconscious and later on I poured water on my head. After the prayer, the Prophet praised and glorified Allah and then said, "Just now at this place I have seen what I have never seen before, including Paradise and Hell. No doubt it has been inspired to me that you will be put to trials in your graves and these trials will be like the trials of Masih-ad-Dajjal or nearly like it (the sub narrator is not sure which expression Asma' used). You will be asked, 'What do you know about this man (the Prophet Muhammad)?' Then the faithful believer (or Asma' said a similar word) will reply, 'He is Muhammad Allah's Apostle who had come to us with clear evidences and guidance and so we accepted his teachings and followed him. And he is Muhammad.' And he will repeat it thrice. Then the angels will say to him, 'Sleep in peace as we have come to know that you were a faithful believer.' On the other hand, a hypocrite or a doubtful person will reply, 'I do not know, but I heard the people saying something and so I said it.' (the same). "

Yahya related to me from Malik from Ziyad ibn Sad that Ibn Shihab said, "Neither jurur, nor musran al-fara, nor adhq ibn hubayq should be taken as zakat from dates. They should be included in the assessment but not taken as zakat. "

Malik said, "This is the same as with sheep and goats, whose young are included in the assessment but are not (actually) taken as zakat. There are also certain kinds of fruit which are not taken as zakat, such as burdi dates (one of the finest kinds of dates), and similar varieties.

Neither the lowest quality (of any property) nor the highest should be taken. Rather, zakat should be taken from average quality property."

Malik said, "The position that we are agreed upon concerning fruit is that only dates and grapes are estimated while on the tree. They are estimated when their usability is clear and they are halal to sell. This is because the fruit of date-palms and vines is eaten straightaway in the form of fresh dates and grapes, and so the assessment is done by estimation to make things easier for people and to avoid causing them trouble. Their produce is estimated and then they are given a free hand in using their produce as they wish, and later they pay the zakat on it according to the estimation that was made."

Malik said, "crops which are not eaten fresh, such as grains and seeds, which are only eaten after they have been harvested, are not estimated. The owner, after he has harvested, threshed and sifted the crop, so that it is then in the form of grain or seed, has to fulfil his trust himself and deduct the zakat he owes if the amount is large enough for him to have to pay zakat. This is the position that we are all agreed upon here (in Madina)."

Malik said, "The position that we are all agreed upon here (in Madina) is that the produce of date palms is estimated while it is still on the tree, after it has ripened and become halal to sell, and the zakat on it is deducted in the form of dried dates at the time of harvest. If the fruit is damaged after it has been estimated and the damage affects all the fruit then no zakat has to be paid. If some of the fruit remains unaffected, and this fruit amounts to five awsuq or more using the sa of the Prophet, may Allah bless him and grant him peace, then zakat is deducted from it. Zakat does not have to be paid, however, on the fruit that was damaged . Grapevines are dealt with in the same way.

If a man owns various pieces of property in various places, or is a co-owner of various pieces of property in various places, none of which individually comes to a zakatable amount, but which, when added together, do come to a zakatable amount, then he adds them together and pays the zakat that is due on them ."

Allah's Apostle said, "Your period (i.e. the Muslims' period) in comparison to the periods of the previous nations, is like the period between the `Asr prayer and sunset. And your example in comparison to the Jews and the Christians is like the example of a person who employed some laborers and asked them, 'Who will work for me till midday for one Qirat each?' The Jews worked for half a day for one Qirat each. The person asked, 'Who will do the work for me from midday to the time of the `Asr (prayer) for one Qirat each?' The Christians worked from midday till the `Asr prayer for one Qirat. Then the person asked, 'Who will do the work for me from the `Asr till sunset for two Qirats each?' " The Prophet added, "It is you (i.e. Muslims) who are doing the work from the `Asr till sunset, so you will have a double reward. The Jews and the Christians got angry and said, 'We have done more work but got less wages.' Allah said, 'Have I been unjust to you as regards your rights?' They said, 'No.' So Allah said, 'Then it is My Blessing which I bestow on whomever I like. "

Yahya related to me from Malik from Zayd ibn Aslam from Ata ibn Yasar from Abdullah as-Sanabihi that the Messenger of Allah, may Allah bless him and grant him peace, said, "A trusting slave does wudu and as he rinses his mouth the wrong actions leave it. As he cleans his nose the wrong actions leave it. As he washes his face, the wrong actions leave it, even from underneath his eyelashes. As he washes his hands the wrong actions leave them, even from underneath his fingernails. As he wipes his head the wrong actions leave it, even from his ears. And as he washes his feet the wrong actions leave them, even from underneath the toenails of both his feet." He added, "Then his walking to the mosque and his prayer are an extra reward for him."

Allah's Apostle said, "It was said to Bani Israel, Enter the gate (of the town) with humility (prostrating yourselves) and saying: "Repentance", but they changed the word and entered the town crawling on their buttocks and saying: "A wheat grain in the hair."