What does this mathematical rebus means ?

I look flat, but I am deep. Hidden realms I shelter. Lives I take, but the food I offer. At times I am beautiful. I can be calm, angry, and turbulent. I have no heart but offer pleasure as well as death. No man can own me, yet I encompass what all men must have. What am I?

What is the riddle which can be asked all day with a different correct answer each time.

We have four gears with below features=> Both Gear A and D has 60 teeth=> Gear B has 40 teeth=> Gear C has 20 teeth=> Every two minutes, Gear B makes 25 full turns.What is the relative speed of Gear A and Gear B?

You have a basket containing ten apples. You have ten friends, who each desire an apple. You give each of your friends one apple.
Now all your friends have one apple each, yet there is an apple remaining in the basket.
How?

Use only one mathematical symbol and all numbers (0-9) to get a sum of 99

Can you find a five letter word that is left with only two letters if one is removed?

Which is heavier: a ton of bricks or a ton of feathers?

Identify the next two numbers in this series.

101, 112, 131, 415, 161, 718, ???, ???

A girl is twice as old as her brother and half as old as her father. In 50 years, her brother will be half as old as his father. How old is the daughter now?