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

Can you solve the rebus below?

What do you call a fish without an eye?

What does the below rebus puzzle mean?

how come the second man dies?

What is more useful when it is broken?

Can you find out which triangle will have a bigger area among the following?
1. A triangle with sides 300, 400 and 500
2. A triangle with sides 300, 400 and 700

Identify The phrase in the picture.

What 4-letter word can be written forward, backward or upside down, and can still be read from left to right?

You are presented with three boxes. One of them has a red ball inside and the other two have a black ball inside each of them. You are asked to pick up the one with red ball and you pick one. Now, one of the other boxes is opened and it is found to have a black ball.

You are presented with a chance to change your box with the one that is left closed. Will you change your box? Why or why not?