It's a protector.
It sits on a bridge.
One individual can see directly through it, while others wonder what it hides.

What is it?

There are six people in a family namely M, N, O, P, Q and R.

R and O are brother and sister.

N is the brother of Q's husband.
P is the father of M and grandfather of R.

How many male members are in the family?

You are given a cube that is made with the help of 10x10x10 smaller cubes summing up to a total of 1000 smaller cubes. You are asked to take off one layer of the cubes.
How many remain now?

People make me, save me, change me, raise me. What am I?

I am written with two letters.
I said with the one.
I usually am seen with the two.

Who am I?

I am never scared but became petrified and can’t live in a house but would die to make one. What am I?

What has six faces, but does not wear makeup, has twenty-one eyes, but cannot see? What is it?

What part of the chicken has the most feathers?

What brings you down but never up?

Can you decipher these quotes by Albert Einstein?
Blf xzm mvevi hloev z kilyovn lm gsv ovevo lm dsrxs rg dzh xivzgvw.