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

For this puzzle, you might have to find logic in something illogical. But hey, it's fun and a healthy little break from your strenuous puzzle-solving sessions.

Can you decipher the meaning in the following cluster of letters?

ITIT,NCENTCENT

Which is faster, Heat or Cold ? Explain.

I got a bee but no honey.
got an eye but am still blind.
got a sea but no water.
got a tea but no coffee.
got a why but no answer.

What Am I?

When we see 2 but call 10?

Where do you go to learn how to make ice cream?

I have branches, but no fruit, trunk or leaves. What am I?

Prove that twice of ten is the same as twice of eleven.

When it's bad luck to meet a black cat?

Prove that the below maths equation is true.

8 + 8 = 91