What does this rebus means ?

PROG WORKRESS

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

A man has eighty-one cows ( numbered 1,2,3...81 as such). The beauty is that cow no. 1 gives 1ltr of milk, cow no. 2 gives 2ltrs of milk and so on. The man wants to equally distribute the cows among his nine sons so that each one of them gets the same quantity of milk.

What can you hold in your right hand, but never in your left hand?

Why is the Hole below a Lock?

Take away the whole and some still remain. What is it?

Most people think of me as money. But when they find me in the water, they won’t get any money out of me. What am I?

I am a number I am not an odd number I am higher than 90 I am not higher than 100 If you subtract me from 100, you get nothing. What number am I?

I know there are two methods by using three time the same number with a plus(+) operator , you can make sum as 60.

One of them is 20+20+20.

whats the other way ?

John buys rice at Rs.60/kg from Britain and then sells them at Rs.5/kg in India. As a result of this, he becomes a millionaire. How come?