What is at the end of a rainbow?

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?

Rearrange the letters in "new door" to make one word.

Next Number in the Series,

5, 16, 49, 104, ?

I purchased an awesome ice cream cone having 5 different flavour scoops.
Five flavours are pistachio, mint-chip, strawberry, marshmallow, and raspberry

I will give u some clues so that you can figure out the order of flavours from bottom to top.
1. The bottom flavour of the cone has 10 letters.
2. The marshmallow scoop is between the pistachio and the mint-chip scoop.
3. marshmallow is the raspberry scoop but below the mint-chip scoop.

So can you figure out the flavour of ice cream in order from bottom to top?

A new Engineering building containing 100 offices had just been completed. John was hired to paint the numbers 1 to 100 on the doors. How many times will John have to paint the number nine (9)?

Find The Missing Number In the Sequence.
6 25 64 ? 32 1

There is an exact a week gap between Christmas and New Year. Hence, It is obvious that the new year that comes right after Christmas comes on the same day of the week.

A Strange thing happened in the Year 1777. Christmas occurs on Wednesday and New Year on Monday. How is that possible?

Find the next number in the series below

21 32 54 87 131 ?

Using Only Five 5's and any mathematical operator make sum as 37