Transform the word THINK into BRAIN while changing only one letter at a time in a manner that each of the word in the process is a real word!!!

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

Why is it against the law for a man living in Delhi to be buried in Mumbai?

You have 21 jars with you. Out of them, 7 are filled with water, 7 are half-full with water and 7 are empty. How will you distribute the jars among three people such that each one of them gets an equal number of jars and an equal amount of water?

How many words can a quill made with the feather of a pigeon write with a 100ml bottle of black ink?

What is the relationship between these matchstick pictures below?

What does an Island and the letter T have in common?

I want to fill my bucket using both cold and hot water.
I have two taps for both cold and hot water. The hot water tap fills the bucket in exact 6 hours and the cold water tap fills the bucket in exact 4 hours.
I turn both of them simultaneously but I forgot to turn off another tap which removes the water out of the bucket. This tap can empty the bucket in 12 hours.

How Long will it take to fill the bucket?

A large container is kept in open under the rain. Every passing hour, the water collected inside the container becomes double what it was.

In ten hours, the container is filled completely. Can you calculate how long would it have taken to be filled in half?

What is the last thing you take off before bed?