What does does this rebus picture means ?

Find the 8 in the below-given Image.

I have nine bottles of wine and one of the nine bottles is poisoned.
I need to find the poisoned bottle with two facts
(1) Poison is deadly, only a sip will cost death
(2) I have two mice to do so.

How should I do it?

Can you count the number of seconds in a year?

Clue: You need to bother about calculation.

See the given image carefully. What you have to do is move the blue checkers in the position of the black checkers and vice versa. You are only allowed to move the checker to an adjacent empty space. Do it in the least possible moves.

Find the missing letter in the last circle logically in the given below picture.

Can you convert the number zero(0) into a positive number using just one mathematical operator ?

Solve this riddle by finding the odd one out from the rest.

Can you count the number of lines in the below picture?

Can you find out which number multiplied by itself will give the output as 12345678987654321?