Can you solve the tricky chess rebus puzzle below by ciphering the hidden meaning?

How many sides does a circle have?

If you remove one from eleven, it becomes ten. If you remove one from nine, it becomes ten.

How is this possible?

A brand new Mobile Phone was on sale at 20% as a promotional offer. By what per cent must the Mobile price be increased to sell it at the original price again?

Two boys were admitted to a school. When the headmaster asks them about their parents, they tell him that they have same parents (father and mother). On further inquiry, it turns out that they both share the same date for their birthday.

"Are you twins," ask the headmaster.
"No," replies the boys.

Is it possible?

Name one eight-letter word with 'kst' in the middle, 'in' the beginning, 'and' at the end.?

What number do you get when you multiply all of the numbers on a telephone's number pad?

Your job is to measure 45 minutes if you have only two cords and matches to light the cords.

1. The two cords are twisted from various materials, so their different segments can burn at different rates.
2. Each cord burns from end to end in exactly one hour.

Describe your way of measuring the 45 minutes.

You have two jars of chocolates labelled as P and Q. If you move one chocolate from P to Q, the number of chocolates on B will become twice the number of chocolates in A. If you move one chocolate from Q to P, the number of chocolates in both the jars will become equal.

Can you find out how many chocolates are there in P and Q respectively?

Make a sentence consisting of three words that have the whole alphabet.