What does below pictogram mean?

Look at the below sequence of letters and tell us what the next letter should be:

O T T F F S S ?

I know a 5-digit number having a property that With a 1 after it, it is three times as large as it would be with a one before it.

Guess the number?

Decode the below four famous ciphers:

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

Which alphabet is a part of our body?

I noticed one of the words in the oxford dictionary is spelled incorrectly. What about you?

John was a very careless driver, so his owner Jacob gave him an offer that he will get an incentive of Rs.30 for every bottle box he delivered without breaking it and he will be charged Rs.90 for every bottle box he broke. Jacob gave John 100 bottles-box to deliver. After delivery, Jacob paid John Rs.2400. How many bottles-box did John break?

Can you count the number of blocks in the picture below?

Identify the hidden meaning behind this picture?

It's a 7-letter word.
If we remove 1 letter from it, it remains the same.
If we remove 2 letters from it, it remains the same.
If we remove 3 letters from it, it remains the same.
If we remove all the letters from it, still it remains the same.
What is it?