What does this rebus means ?

How many sides does a circle have?

While house hunting in London, I came across a very good leasehold property Discussing the lease the landlady told me:

'The property was originally on a 99 years lease and two-thirds of the time passed is equal to four-fifths of the time to come. Now work it out for yourself and see how many years are to go!

Name one eight-letter word with 'kst' in the middle, 'in' the beginning, 'and' at the end.?

There is an English word that can be used up to four times in a row without modifying the spelling and form a valid grammatical sentence.

Do you know what word is that?

I am the one who remains awake when you sleep. But I need to rest when you awake. Who Am I?

You see a mathematical expression in the picture. Can you think of a movie that this expression refers to?

The following alphametic has only one solution. Can you find it?
ENLIST + SILENT + LISTEN = ANAGRAM

PS: You may start the number from 0.

How many Watermelons are there in the below picture?

There are six people in a family namely M, N, O, P, Q and R.

R and O are brother and sister.

N is the brother of Q's husband.
P is the father of M and grandfather of R.

How many male members are in the family?