Using Only Five 5's and any mathematical operator make sum as 37

Replace the question mark with the correct number.

A rubber ball keeps on bouncing back to 2/3 of the height from which it is dropped. Can you calculate the fraction of its original height that the ball will bounce after it is dropped and it has bounced four times without any hindrance ?

Can you find the missing letter in the sequence?
S - T - I - L - ? - T - F - Y - C

Replace the (?) with the correct mathematical signs to make the expression equal to 59.

18 ? 12 ? 4 ? 5 = 59

Forwards I am heavy, backward I am not. What am I?

You find yourself in a strange place guarded by two guards.One of the guard always say truth while other always lies.You don't know the identity of the two.You can ask only one question to go out from there. What should you ask?

They are the five precious gems of an everyday sort and all can be found on a Tennis Court. Who are they?

I’m tall when I’m young, and I’m short when I’m old. What am I?

Before reading ahead, you must know the fact that only one of the people here is telling the truth.

A says that B is lying.
B says that C is lying.
C says both A and B are lying.

Can you find out who is speaking the truth?