What always comes into a house through the keyhole?

Can you think of any three-dimensional shape that comprises of exactly two surfaces?

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

Can you find the number?

What has no start, end, or centre?

What Does this text mean:

important=important

How can you drop a raw egg from a height onto a concrete floor without cracking it?

Can you solve the below geography rebus by decoding the below rebus ?

You are stuck on an island where you have nothing. You find four pieces of paper somewhere on the island. What will be your strategy to escape from the island safely?

PS: No other resource is available to you on the island, neither can you build anything.

Christina is older than Kareena and Karishma. Katrina is older than Karishma and younger than Kareena. If Kareena has a brother named John, who is older than Christina, who's the youngest?

Below, you can see some coding:
January = 1017
February = 628
March = 1335
April = 145
May = 1353
June = 1064
July = 1074
August = 186

Now deciphering the way it has been coded, can you find out how September will be coded?