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

You may enter, but you may not come in. I have space, but no room. I have keys, but open no lock. What am I?

A Child was born in Lahore, Pakistan. Still, the child is not a Pakistani citizen. why?

10 people came into a hotel with 9 rooms and each guest wanted his own room. The bellboy solved this problem.
He asked the tenth guest to wait for a little with the first guest in room number 1. So in the first room, there were two people. The bellboy took the third guest to room number 2, the fourth to number 3, ..., and the ninth guest to room number 8. Then he returned to room number 1 and took the tenth guest to room number 9, still vacant.
How can everybody have his own room?

Can you Find and name the hidden bird in the picture below ?

What is the fastest way to double your money?

Place a mathematical symbol between the numerals 5 and 9 in such a way that the resulting number is greater than 5 but smaller than 9.

_ _ _ IE _ _
_ _ _ IE _
_ _ IE _ _
_ _ IE _
_ _ _ _ IE

Like you see, some letters have gone missing from these words that contain the IE pair at some or the other place. The letters that will be used to fill the blanks are given below. Use them and form meaningful words. Can you do that?

A, C, D, F, H, K, L, M, N, N, O, R, R, S, S, S, T, T, Y and Y.

Buy me, smell me or deliver me, I do not change.

Who am I?

John named his first son Alpha, second Beta, third Charlie and fourth Delta. What is the fifth son's name?