Can you start the fire using two pieces of wood?

Find The Next Number in this series.
1, 2, 6, 42, 1806 ?

Three doctors said that Bill was their brother. Bill says he has no brothers. How many brothers does Bill actually have?

What has one letter and starts with an E?

There is a square of a particular number which when doubled, becomes 7 more than its quarter.

Can you find the number?

I taste better than I can smell. Who am I?

This is a classy optical illusion puzzle. What more you can find except bricks in the image below?

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

Using the clues below, what four numbers am I thinking of?

The sum of all the numbers is 31.
One number is odd.
The highest number minus the lowest number is 7.
If you subtract the middle two numbers, it equals two.
There are no duplicate numbers.

What will be the best approach to finding all the prime numbers less than 75 that leave an odd reminder when we divide them with 5?