Which is the correct shadow of the bird?

I am the fastest animal but cannot climb the tree. What 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 ?

Count The number of F's in the paragraph below:

"FINISHED FILES ARE THE RESULT OF YEARS OF SCIENTIFIC STUDY COMBINED WITH THE EXPERIENCE OF YEARS"

I have a clock(12-hour format) and both the needles of the clock overlap at 12:00.
After how much time, they will overlap again?

If 5 cats catch 5 mice in 5 minutes, how long will it take one cat to catch a mouse?

Always in you, Sometimes on you;

If I surround you, I can kill you.

What am I?

During which month do people sleep the least?

The more you take me, the more you leave me behind.
Who Am I?

Pronounced as one letter,
And written with three,
Two letters there are,
And two only in me.
I am double, I am single,
I am black blue and grey,
I am read from both ends,
And the same either way.