What has many keys but can’t open a single lock?

What is the word or phrase?

My cousin lives in one story house in Antarctica. His house is made the of-of sandstone. what is the color of stairs?

At my favorite fruit stand,
an orange costs 18,
a pineapple costs 27,
and a grape costs 15.
Using the same logic, can you tell how much a mango costs?

I was speeding and ran through a stop sign, yet two traffic officers who were there do nothing about it.

why?

P is the father of Q and S is the son of R. T is the brother of P and has a daughter U. If R is the sister of P, then what is the relation between U, Q and S?

In one of the popular batman series movie "Batman Forever", there was a riddle that goes like "Tear me off and then scratch my head and I was red then and now I am back. Who am I?

A container contains 100 eggs. They can be either fresh or rotten. What is sure is the fact that there is at least one fresh egg in that container.

If you are asked to pick two eggs randomly from the container, at least one of them will be rotten.

Can you calculate how many eggs in that container are fresh?

Find The Next Number In The Sequence

30 10 15 13 0 16 -15 ?

Can you find out what is missing?

1 3 5
2 4 ?

Hint: It's not six. Think out of the box.