What English word has three consecutive double letters?

Write the next letter in this sequence.
O, T, T, F, F, S, S, E, __
**Hint: It is a Number Series Puzzle

The great emperor Akbar once ruled India. He was well known for his intelligence. But along with that, he was known for the Nine Gems in his court. One of the nine gems was Birbal, a quick witted and extremely intelligent man. The stories of his wit were widely popular.

Once a king ruling in a distant land heard of Birbal. To check his wit, he sent an invitation and called him to visit his land. Akbar allowed Birbal to go and he took off on the journey.

Upon reaching that kings kingdom, he was welcomed with flowers. He was then escorted to the palace of the king. Upon entering the palace, Birbal found that there were six people sitting in front of him adorning the same robe. They were also lookalike and it was hard to judge who the real king was.

After a couple of minutes, Birbal approached one of them and bowed in front of him greeting him.

That was the real king. How did Birbal know who was the real king ?

If,

A = 1

B = 2

C = 3

...

...

Z = 26.

Based on above rule, you need to find an eleven letter word whose letter sum is equal to 52.

'S' refers to the number of seconds in a day and 'H' refers to the number of hours in ten years. Which quantity out of these two is greater?

what does the below math rebus puzzle mean?

What has many teeth, but cannot bite?

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

A man always keeps a spare tyre in his car. To make full use of all the five tyres, he changes the tyres in a manner that for a distance of 1, 00,000 km, each of them runs the same distance.

Can you calculate the distance travelled by each tyre on that journey?

There is a square of a particular number which when doubled, becomes 7 more than its quarter.

Can you find the number?