Find The Next Number In The Sequence

30 10 15 13 0 16 -15 ?

How can you make the following equation true by drawing only one straight line: 5+5+5=550 ?

Can you place three balls such that the equation shown in the picture holds true?

There are 4 big houses. They are made from the materials: red marble, green marble, white marble and blue marble.

* Mrs Jennifer's house is somewhere to the left of the green marble one and the third one alone is white marble.
* Mrs Sharon owns a red marbles house and Mr Cruz does not live at either end, but lives somewhere to the right of the blue marbles house.
* Mr Danny lives in the fourth house, while the first house is not made from red marble.

Who lives where, and what is their house made from?

Find the next number in the series?
2, 12, 36, 80, 150, 252, 392, _ ?

I am a type of word that is spelt incorrectly or used differently, on purpose for humour. What am I?
Hint 1: You can find me in a joke.
Hint 2: I am a play on words.

Open a Laptop which is password protected. Hint for the password is given as below:

1 mobile 3 books 2 Boards 1 night 4 balls 2 lighters 1 ghost 1 hat 3 watches

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

I have an eye but still cannot see.

Who am I?

I have a hole in my back and legs I lack.
I live where I can’t breathe and I eat without teeth.
What am I?