If 21x = 79x, what is the value of x?

I am a seven-letter word but if you remove four of my letters I will have one left. What word am I?

Do you know of a place where the wind blows south and then suddenly shifts direction towards the north?

What has 13 hearts but no other organs?

You need to pick one entry from pot A and one from pot B to have a perfect match. Can you do it?

The barber of Town shaves all men living in the town. No man living in the town is allowed to shave himself. The barber lives in that town. Who then shaves the barber of the town?

Can you count the number of triangles in the given figure?

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.

A brand new Mobile Phone was on sale at 20% as a promotional offer. By what per cent must the Mobile price be increased to sell it at the original price again?

He does not have any heart but still, He manages to live.
If you kill him, you will eventually die but yet you kill him.
He cannot run, who is He?