Rephrase the sentences using the modal verbs must, may, can or

Rephrase the sentences using the modal verbs must, may, can or cant.
1 I dont know about his plans for this weekend. It is possible that he will be busy.
2 Im sure that Johnny is fifteen now. I remember his birthday party five years ago. There were ten candles.
3 I dont believe that he is ill. I saw him at the stadium only ten minutes ago and he was playing volleyball.
4 Ill never believe that the boy in the red T-shirt is Mike. Mike never wears red.
5 Jason speaks three languages, plays the piano and the guitar and is very good at mathematics and physics. Im sure that he is very talented.
6 The plane for the flight from London to New \brk took off an hour ago. It is certainly over the Atlantic by now;