Using Only Five 5's and any mathematical operator make sum as 37

You throw me out when you want to use me and you take me in when you don't want to use me.

Who Am I?

If,

1 = 5 ,
2 = 25 ,
3 = 325 ,
4 = 4325

Then, 5 = ?

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?

Many have heard it, but nobody has ever seen it, and it will not speak back until spoken to. What is it?

A charming young lady was approached by a kind looking old woman in a restaurant. The old woman said to her, 'You look exactly like my younger daughter. Sadly she passed away a couple of months back. Could you do me a favor and say 'Goodbye, mother' with a kind smile on your face when I leave?

The young lady agreed for the same and said, 'Goodbye, mother' when the old woman left. Soon after, she got the most disengaging shock of her life.

Can you guess what the shock was?

John can eat 27 chocolates in an hour, Jacob can eat 2 chocolates in 10 minutes, and Jolly can eat 7 chocolates in 20 minutes. How long will it take them to share and eat a box of 120 chocolates whilst playing Chess?

Why blonde cannot dial 911?

Can you find out which options fits best with the missing column?

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