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

If,

A = 1

B = 2

C = 3

...

...

Z = 26.

Based on above rule, you need to find an eleven letter word whose letter sum is equal to 52.

John’s parents have three sons: Snap, Crackle, and what’s the name of the third son?

I go up and I go down.
I go up towards the beautiful sky and down toward the green ground.
I am present tense.
I am past tense too
Children love me.

Who Am I?

Can you find the missing piece of the Porsche?

I know there are two methods by using three time the same number with a plus(+) operator , you can make sum as 60.

One of them is 20+20+20.

whats the other way ?

Always in you, Sometimes on you;

If I surround you, I can kill you.

What am I?

When my father was 31 I was 8. Now he is twice as old as me. How old am I?

Can you spot what's wrong with the following sentence?

PETER WAS ANGRY AT
HIMSELF BECAUSE HE
ACCIDENTALLY LEFT THE
THE KEYS TO HIS CAR
AT HIS FRIEND'S HOUSE.

Before Mount Everest was discovered, what was the highest mountain in the world?