Can you fill the blank with the correct number?

6 30 870 756030 _____

If,

20 % 5 = 24

21 % 7 = 33

42 % 6 = 67

Then;

66 % 6 = ?

A man who was outside in the rain without an umbrella or hat didn’t get a single hair on his head wet. Why?

You are confined in a room and given two metal rods. Out of these two rods, one is magnet and the other is the iron rod. They look starkly similar. You don't have any other metal object in the room.

How will you decide which one of those is magnet?

What is the coolest letter in the alphabet?

Take one out and scratch my head, I am now black but once was red. What am I?

Considering the below equation:

V + II - VI = 10
IV - X + VIII = 20
IV - VII + VI = 30

Then, I + II + III = ?

John decided to give his bike 3 coats of paint. Which coat would go on the first?

Do you know who was buried in John's tomb?

Find the missing letter in the last circle logically in the given below picture.