I have teeth but i don't bite. Who Am I ?

what does this below rebus represent identXQQQQQME

I am quite hot but become too cold if you remove the first two letters. What am I?

I have an apple tree , number of apple in this tree get doubles every week.

On 30th week , the tree gets completely filled with apples :-)



Can you tell me , on what week does my tree is half covered with apples ?

In an Art Gallary, When the clock hit 11 am, Artist hung the painting number 30. When it struck 4 pm, he hung painting number 240 and when it struck 7:30 pm, he hung painting number 315.

Can you determine, which painting number will he hang when the time is 9:20 pm?

When my father was 31 I was 8. Now he is twice as old as me. How old am I?

Take away my first letter, then take away my second letter. Then take away the rest of my letters, yet I remain the same. What am I?

What occurs twice in a week, once in a year but never in a day?

There's one "sport" in which neither the spectators nor the participants know the score or the leader until the contest ends.

What is it?

The teacher told the student that if he told a lie then he will be expelled from school and if he told the truth then he still is expelled from school.

What can a student say to prevent his being expelled from school?