Find The Next Number In The Sequence

30 10 15 13 0 16 -15 ?

What is so fragile that saying its name breaks it?

What is the Surname of Barbie Doll?

What question can you never answer yes to?

A man is trapped in a room. The room has only two possible exits doors. Through the first door there is a room constructed from magnifying glass. The blazing hot sun instantly fries anything or anyone that enters. Through the second door there is a fire-breathing dragon. How does the man escape?

What number do you get when you multiply all of the numbers on a telephone's number pad?

If eleven plus two equals one, what does nine plus five equal?

I add 5 to 9 and get 2. The answer is correct, so what am I?

A boy and a girl are sitting on the porch.
"I'm a boy," says the child with black hair.
"I'm a girl," says the child with red hair.
If at least one of them is lying, who is which?

Twenty frogs are sitting on a log floating on the surface of a river. Two of them decide to jump off into the water.

How many frogs are there on the log at this moment?