How many triangles can you find in this given picture?

Can you convert the number zero(0) into a positive number using just one mathematical operator ?

The more you take me, the more you leave me behind.
Who Am I?

John was working on a Chemical Mixture whose weight comprise 90% liquid and 10% solid. The total weight of the mixture is 20 pounds. After a while, John noticed that some of the liquid evaporated and now the liquid comprises just 50% of the weight.

What is the weight of the chemical mixture now?

Count the number of triangles in the picture below:

The following four words might seem abrupt to you. But you can make them meaningful by just adding vowels.
RDSH
GGPLNT
TMT
NN

Hint: All of them are vegetables.

What can run but never walks, has a mouth but never talks, has a head but never weeps, has a bed but never sleeps?

Which country gets ill every time?

What is next number in the pattern below:

131 517 192 123 ?

What's the only room from which no one can enter or leave