When 99 is considered higher than 100?

Decode the below four famous ciphers:

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

What brings you down but never up?

Decode below three cipher riddles:

26 L of the A
7 D of the W
1000 Y in a M

If in a code language, DISTANCE is written as IDTUBECN and DOCUMENT is written as ODDVNTNE, the how will THURSDAY be coded as in the same language?

Can you solve below mathematical equation?

2^1234 - 2^1233

An express train takes 3 seconds to enter the tunnel which is 1 km long.
If it is travelling at 120 km an hour, how long will it take to pass completely through the tunnel?

I speak without a mouth, and hear without ears. I have no-body, but I come alive with the wind. What am I?

I am green and found in the forest and have needles instead of leaves. What am I?
Hint 1: It can be used for Christmas decorations.
Hint 2: I have a strong, scent that is used in air fresheners.

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