Why is Saturday stronger than Monday?

Can you solve this amazing hard number series problem?
7, 8, 10, 12, 16, 18 ?

What does this mean?

CCCCCCC

Replace the question mark in the picture below.

Find the next number in the series

12, 20, 40, 72, 116, 172 ?

You are an expert on paranormal activity and have been hired to locate a spirit haunting an old resort hotel. Strong signs indicate that the spirit lies behind one of four doors. The inscriptions on each door read as follows:

Door A: It's behind B or C
Door B: Its behind A or D
Door C: It's in here
Door D: It's not in here

Your psychic powers have told you three of the inscriptions are false, and one is true. Behind which door will you find the spirit?

What does this rebus puzzle means ?

Below the four parts have been reorganised. The four partitions are exactly the same in both arrangements. Why is there a hole?

Can you start the fire using two pieces of wood?

Which alphabet is a part of our body?