I look at you, you look at me, I raise my right, you raise your left. What am I?

Decode the below four famous ciphers:

8P of the SS
1M of the E
1S of the SS
60M in 1H

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

Find a 9-digit number, which you will gradually round off starting with units, then tenth, hundred etc., until you get to the last numeral, which you do not round off. The rounding alternates (up, down, up ...). After rounding off 8 times, the final number is 500000000. The original number is commensurable by 6 and 7, all the numbers from 1 to 9 are used, and after rounding four times the sum of the not-rounded numerals equals 24.

In the picture that is attached with this question, you can find a square which comprises of four little squares inside it. Consider this square to be made with matchsticks. You have to remove two matchsticks such that only two squares remain instead of five.How will you do it ?

What's the next in the series?

H, Be, F, S, Mn, Kr, In, Gd, Tl, ?

What is both possible and impossible at the same time?

How many people must be gathered together in a room, before you can be certain that there is a greater than 50/50 chance that at least two of them have the same birthday?

What is the next shape from answers A, B, C, and D figure?

A man who was outside in the rain without an umbrella or hat didn’t get a single hair on his head wet. Why?