What does this mathematical rebus means ?

Can you name an animal whose killing cannot be performed without spilling your own blood?

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

What is wrong in the below Picture?

A generous owner of a company decided to give a bonus of $45 to every man and $60 to every woman on his birthday. But only one-ninth of the men and one-twelfth of the women were present to take the bonus.

Can you calculate the amount of money the owner spent if there were 3552 employees?

What always comes into a house through the keyhole?

Move four matchsticks to the below square to form three squares?

O_er_t_o_

Complete the missing letters of the given word.

In the Thar desert, 3 men found a big 24L Jar is full of water. Since there is a shortage of water so they decided to distribute the water among themselves such that they all have equal amounts of it. But they only have a 13L, a 5L and an 11-litre Jar.

How do they do it?

A red house is made out of red bricks. A yellow house is made out of yellow bricks. And, a blue house is made out of blue bricks. So, what is a greenhouse made of?