I am the one who remains awake when you sleep. But I need to rest when you awake. Who Am I?

John can eat 27 chocolates in an hour, Jacob can eat 2 chocolates in 10 minutes, and Jolly can eat 7 chocolates in 20 minutes. How long will it take them to share and eat a box of 120 chocolates whilst playing Chess?

I am the black child of a white father, a wingless bird, flying even to the clouds of heaven. I give birth to tears of mourning in pupils that meet me, even though there is no cause for grief, and at once on my birth, I am dissolved into air. What am I?

Can you count the number of triangles in the picture below?

How can you make the following equation true by drawing only one straight line: 5+5+5=550 ?

What has one eye, but can’t see?

Six glasses are in a row. The first three are filled with milk and the last three are empty. By moving only one glass, can you arrange them so that the full and the empty glasses alternate?

John said, "If yesterday was tomorrow, today would be Friday."

When did John make this statement?

Solve the following series:
AZ, GT, MN, __, YB

How many sides does a circle have?