How many sides does a circle have?

I came first on earth but second on the heaven.
I also came twice in a week but found just once in a year.
I stay away from months but you can find me in February.

What am I?

Seven Robbers robbed a bank and hide the coins in a lonely place.
They decide to divide the money equally the next morning. Two greedy robbers decided to cheat the others and reach the place at night. They equally divided the coins between them, one coin left. So they called another robber and then they decided to divide equally among the three. Sadly again one coin left. The same thing happened to the 4th 5th and the 6th robber.
However, when the 7th robber reached in the morning, they can divide the coins equally.

How many coins were there in total?

Pronounced as one letter,
And written with three,
Two letters there are,
And two only in me.
I am double, I am single,
I am black blue and grey,
I am read from both ends,
And the same either way.

If six children and two dogs were under an umbrella, how come none of them got wet?

I am a white box having no key or lid.
Yet there is a golden treasure inside it.

What Am I?

Two in a corner, one in a room, zero in a house, but one in a shelter. What is it?

I sleep during the day and fly at night, but I have no feathers to aid my flight. What am I?

How many times can you subtract the number two from the number fifty?

What has six faces, but does not wear makeup, has twenty-one eyes, but cannot see?