Find The Next Number In The Sequence

30 10 15 13 0 16 -15 ?

What is the relationship between these matchstick pictures below?

Count the number of squares in the picture below.

I look at you, you look at me I raise my right, you raise your left. What am I?

Why 1729 is a magic number? Answer Logically.

What are the next two letters in the following series and why?
W A T N T L I T F S _ _

*Hint: Check Puzzle Title

Who can jump higher than a Mountain?

By moving just one matchstick, you need to make the below statement true. Can you do it?

The doctor prescribed you to take one pill from the bottle every half an hour. The bottle is now left with only three pills.

How long do you think you have before you run out of pills?

Can you arrange four 9's and use at most 2 math symbols, to make the total 100?