Which is the correct shadow of the bird?

A certain street contains 100 buildings. They are numbered from 1 to 100. How many 9's are used in these numbers?

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?

Twenty frogs are sitting on a log floating on the surface of a river. Two of them decide to jump off into the water.

How many frogs are there on the log at this moment?

I get hot but I never sweat,
I cook food but I am not a chef,
I have a door but you can't enter me,
I have a light but I am not a lamp.
Who am I?

Give it food and it will live; give it water and it will die.

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.

Why 1729 is a magic number? Answer Logically.

I have an eye but still cannot see.

Who am I?

If a wheel has 54 spokes, how many spaces are there between the spokes?