Quickly Solve this riddle

7 - 4 + 3 * 0 + 1 = ?

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

A wooden log balances equally on the scales when weighed with three-quarters of a pound and three-quarters of a wooden log.

Can you calculate the weight of the entire wooden log?

In a chess board, the queen piece can move horizontally, vertically and diagonally freely. The picture represents the same.Can you place 8 queens on the board in a manner that none of the queens can attack each other?

Baseball bat and ball cost $100. If the bat cost $99 more than the ball, what is the cost of each?

If,
9 * 8 * 7 = 65
8 * 7 * 6 = 50
7 * 6 * 5 = 37

Find
6 * 5 * 4 = ?

Can you find the dog hidden in a group of pandas?

What does below chemistry rebus means?

What are the next two letters in the following series and why?
W A T N T L I T F S _ _

*Hint: Check Puzzle Title

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