I speak without a mouth, and hear without ears. I have no-body, but I come alive with the wind. What am I?

What is the next number in this series?

4,12,84,3612....

A woman lives in a skyscraper thirty-six floors high and is served by several elevators which stop at each floor going up and down. Each morning she leaves her apartment and goes to one of the elevators. Whichever one she takes is three times more likely to be going up than down. Why?

Can you find out the missing number?

? 4 5 3 5

9 5 7 10 3

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

Can you find the number?

What does below Rebus mean ?

esgg sgeg gegs gsge

You are given 2 eggs.
You have access to a 100-storey building.
Eggs can be very hard or very fragile means it may break if dropped from the first floor or may not even break if dropped from 100th floor, Both eggs are identical.
You need to figure out the highest floor of a 100-storey building an egg can be dropped without breaking.
Now the question is how many drops you need to make. You are allowed to break 2 eggs in the process

What is greater than gold but cannot be bought. it can never be sold and can earn if its sought. though it can be broken, it can still be fixed. for by birth it can't start nor by death it is ended.what am i?

I am a normal creature, but I have five hands. I can even have more but even then I will be considered normal.

Who am I?

How many letters are in the alphabet?