If you had a pizza with crust thickness 'a' and radius 'z', what's the volume of the pizza?

Can you replace the question mark with the correct number?

Decode this picture on T-Shirt and tell what it says ?

Doctor Alex and a bus driver John are both in love with the same woman named Olivia. The bus driver need to go for a long trip of 10 days, Before he left he gave Olivia 10 apples.

What does the below mathematical rebus mean?

A man hijacks an aeroplane transporting both passengers(8 of them) and valuable cargo. After taking the cargo, the man demands nine parachutes, puts one of them on, and jumps, leaving the other eight behind. Why did he want eight?

One absent-minded ancient philosopher forgot to wind up his only clock in the house. He had no radio, TV, telephone, internet, or any other means for telling time. So he travelled on foot to his friend's place a few miles down the straight desert road. He stayed at his friend's house for the night and when he came back home, he knew how to set his clock. How did he know?

A man who was outside in the rain without an umbrella or hat didn’t get a single hair on his head wet. Why?

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

What does this rebus means ?