Solution:

A Tongue

Solution:

3.4142788e+29

The biggest number using four 2s will be:
22^22

Solution:

Explanation:

Since Rohini is 21st from either side, there must be 20 people in front of her and 20 people behind her.
20 + 20 + 1 (she herself) = 41
Therefore, the queue consists of 41 people.

Solution:

No stairs, Its a one story building.

Solution:

I am matchstick.

Solution:

You should choose the second shop.

It's a common logic. In the first shop, the barber had neat hairs. Since there are only two barbers in the entire town, he must have got his hairs cut from the barber in the second shop.

Solution:

He asks, "if the mystical stone is not in the East, I s it in the West?"
Possible reply by Mola Ram
1. Yes: mystical stone is in the west.
2. No: mystical stone is east.
3. I don't know: mystical stone is North.

Solution:

The police officer knows the story was not true since Vasco was shot from back and he was injured only in the stomach.

Solution:

Puzzle solved as shown in pic below

Solution:

You must chose the electric chair because there is no electricity in the house and thus you will survive.