What is full of holes but still holds water?

An equation has been laid down using a few matchsticks. However, as you can see, the equation is not correct. Can you correct the equation if you are allowed to add or remove 5 matchsticks?

What occurs twice in a week, once in a year but never in a day?

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

What can jump higher than a building?

A word I know has six letters it contains, remove one letter and 12 remain. What is it?

Which digit occurred maximum times between the number 1 and 1000?

In the Chess Board picture below white army is arranged. You need to add a black army on the board such that no piece is under any threat.
Note: Army comprised of 1 king, 1 queen, 2 rooks, 2 bishops, 2 knights, and 8 pawns.

My thunder comes before the lightning; my lightning comes before clouds; my rain dries all the land it touches. What am I?

You are stuck on an island where you have nothing. You find four pieces of paper somewhere on the island. What will be your strategy to escape from the island safely?

PS: No other resource is available to you on the island, neither can you build anything.