Can you replace the question mark with the correct number?

How can you throw a ball as hard as you can and have it come back to you even if it doesn't hit anything there is nothing attached to it and no one else catches or throws it.

If 5 cats catch 5 mice in 5 minutes, how long will it take one cat to catch a mouse?

The product of three consecutive numbers is 7980.
Then the sum of these consecutive numbers would be?

What is black when you buy it, red when you use it, and gray when you throw it away?

If Japan and Panama decided to merge into a single country, probably people will name it Japanama.

Can you think of two more such country's unions that could produce similar names like Japanama by overlapping their three letters?

How many sides does a circle have?

A non-stop marathon is the shared favourite sport of three brothers.

*The oldest one is fat and short and trudges slowly on.
*The middle brother's tall and slim and keeps a steady pace.
*The youngest runs just like the wind, speeding through the race.

"He is young in years, we let him run!" the other two brothers explained, "'because though he is surely number one, he is second, in a way." Why is it?

John was drowned by he was not wet. How?

What is in seasons, seconds, centuries and minutes but not in decades, years or days?