Complete the table series riddle by finding the number that can replace "??".

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?

I possess a head

I flaunt a tail

But I don't have mouth or legs

Can you find out who I am?

You walk into a room that contains a match, a kerosene lamp, a candle and a fireplace. What would you light first?

There is so small cabin inside a deep forest.
All the forest burned out to worst possible but the inside of the cabin is still the same.
However all the person inside the cabin die.

How come ?

John can fit six large chocolate boxes or nine small chocolate boxes into a carton. How many cartons will he require to put sixty-six chocolate boxes into?

No matter how little or how much you use me, you change me every month. What am I?

If it took eight men ten hours to build a wall, how long would it take four men to build it?

You are given a cube that is made with the help of 10x10x10 smaller cubes summing up to a total of 1000 smaller cubes. You are asked to take off one layer of the cubes.
How many remain now?

What is 3/7 chicken, 2/3 cat and 2/4 goat?