why number 8549176320 is one of a kind?

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?

Can you write down eight eights so that they add up to one thousand?

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?

Can you find out the remainder when 3^300 is divided by 5?

What number comes next in the series?

5 15 5 18 5 24 14 20 _

A man wants to cross the pit of fire which is 25 feet in length and he has 2 planks(fire resistant) 19 feet in length. How can he cross the pit of fire alive?

What does Alexander the Great and Winnie the Pooh have in common?

In the below-given picture of a pretty girl, there is something wrong. Can you find out what it is?

In a rainy season, one day 3 huge ladies walked under a normal-sized umbrella.
The umbrella is not huge enough to accommodate all 3 ladies yet not a single lady got wet. Why?