I am not alive, but I grow; I don't have lungs, but I need air; I don't have a mouth, but water kills me. What am I?

What goes up but never comes down?

I am a word that begins with the letter “i.” If you add the letter “a” to me, I become a new word with a different meaning, but that sounds exactly the same. What word am I?

Prove that twice of ten is the same as twice of eleven.

A 52% bias toss for head using the 51% tail bias coin was done to obtain a fair result.

Can you find how bias is the floor in this case?

What breaks yet never falls, and what falls yet never breaks?

If you drop me I’m sure to crack, but give me a smile and I’ll always smile back. What am I?

using four eights (8) and a one (1) and one mathematical symbol , create the number 100

The dirtier I get, the whiter I look. Who am I?

I am a type of food that is often found in the fridge and can be white in colour. What I am?
Hint 1: I am a dairy product.
Hint 2: You can spread me on the bread.