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

It can't be seen, can't be felt, can't be heard, and can't be smelt.
It lies behind stars and under hills, And empty holes it fills.
It comes first and follows after, Ends life, and kills laughter.
What is it?

In a certain bank, a man deposits a certain amount. According to the bank policies, the amount will be doubled up in a year but as the service charge, they will also deduct Rs. 65 by the end of every year.

If after the 6th year, the amount becomes 0, what do you think is the original amount he deposited in the bank?

Can you start the fire using two pieces of wood?

I am taken from a mine and shut up in a wooden case, from which I am never released, and yet I am used by almost every person. What am I?

How high do you have to count before you use the letter “a” in the English spelling of the whole number?

Count the number of times the letter "F" appears in the following paragraph:

FAY FRIED FIFTY POUNDS OF
SALTED FISH AND THREE POUNDS
OF DRY FENNEL FOR DINNER FOR
FORTY MEMBERS OF HER FATHER'S FAMILY.

Why did the Girl throw the butter out of the window?

I noticed one of the words in the oxford dictionary is spelled incorrectly. What about you?

A pond had 60 fish, out of which, all but 20 died.
How many fishes are now present in that pond?