What you cannot hold but it is yours?

A professor thinks of two consecutive numbers between 1 and 10.
'A' knows the 1st number and 'B' knows the second number

A: I do not know your number.
B: Nor do I know your number.
A: Now I know.

What are the four solutions for this?

Can you identify if it's a murder or a suicide ?

Can you count the number of squares in the given picture?

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 is more useful when it is broken?

How many bananas can you eat if your stomach is empty?

Here is a mathematical expression that also secretly tells a movie name. What movie is that?

When Jack was six years old he hammered a nail into his favourite tree to mark his height. Ten years later at age sixteen, Jack returned to see how much higher the nail was. If the tree grew by five centimetres each year, how much higher would the nail be?

How is the moon similar to a dollar?