Identify the hidden meaning behind this picture?

Place the numbers from 1 to 9 in the circles in a manner that each side of the triangle sums up to 17.

What 5-letter word typed in all capital letters can be read the same upside down?

A man is found hanging dead from the ceiling of a room. The room’s dimensions are 15 x 15 x 15. The man is only 6ft tall and the rope was only 2ft long. There are no windows and only one door to the room. The door is bolted shut from the inside, and a puddle of water is under the man. How did he kill himself?

You bought me for dinner but never eat me. What am I?

Until it is measured, not known. Yet how you miss it when it has gone. What is it?

I look at you, you look at me I raise my right, you raise your left. What am I?

Do You See It?

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?

Replace the question mark with the number below given a simple math problem.