Why is Saturday stronger than Monday?

How can you take 2 from 5 and leave 4?

Give it food and it will live; give it water and it will die.

I have four wings but can't fly.
I express no emotions.
I am found on the exact spot every time you look.
I keep toiling away with a little sound.

Do you know what am I?

Place a mathematical symbol between the numerals 5 and 9 in such a way that the resulting number is greater than 5 but smaller than 9.

Decode below rebus
D
N
A
T
S , D

Forwards I am heavy, backward I am not. What am I?

I come in different shapes and sizes.
Parts of me are curved, other parts are straight.
You can put me anywhere you like,
but there is only one right place for me.
What am I?

Is the statement valid that it does not matter how much older a sibling is, eventually the younger one will be half as old as the older one?

If there are fifteen crows on a fence and the farmer shoots a third of them, how many crows are left?