I get hot but I never sweat,
I cook food but I am not a chef,
I have a door but you can't enter me,
I have a light but I am not a lamp.
Who am I?

In a competitive exam, each correct answer could win you 10 points and each wrong answer could lose you 5 points. You sat in the exam and answered all the 20 questions, which were given in the exam.
When you checked the result, you scored 125 marks on the test.

Can you calculate how many answers given by you were wrong?

Suppose we lay down two cups in front of you. One of the cups is filled with tea and the other one with coffee. Now we ask you to take a spoonful of tea and mix it with the coffee. At this moment, the coffee cup has a mixture of tea and coffee. You have to take that mixture (spoonful) and add it back to the tea.

Can you now tell if the cup of coffee has more tea or the cup of tea has more coffee?

How many cubic feet of dirt are in a hole of one foot deep, three feet long, and two feet wide?

What is the fastest way to double your money?

John is the son of Jacob.
So,
Jacob is the_____of John's father?

Until it is measured, not known. Yet how you miss it when it has gone. What is it?

What is next number in the pattern below:

131 517 192 123 ?

Which Travels Faster? Solve below famous picture riddle:

A donkey is behind another donkey
I'm behind that second donkey
But there is a whole nation behind me

It is a murder you can describe in a word.