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

An evil man kidnapped someone and made them take one of two pills. One was harmless, but the other was poisonous. Whichever pill the victim took, the kidnapper took the other one. The victim took their pill with water and died. The kidnapper survived. How did the kidnapper get the harmless pill?

If nine thousand, nine hundred nine dollars is written as $9,909,
how should twelve thousand, twelve hundred twelve dollars be written?

Can you replace the question mark with the correct number in the below table sequence?

John, a 5-year-old boy, was really fond of the chocolates. He asked his Mother to give him some money to buy his favourite chocolates. His Mother gave him $45. He went to the shopkeeper and asked, "How much is one chocolate for?". The shopkeeper said $3 for one chocolate. Also, if you give me the wrappers of three chocolates, I will give you one for the exchange.
In total, how much chocolate could John eat?

Can you place six matchsticks in a manner that each of the matchsticks is in touch with the other five matchsticks?

If you were to put a coin into an empty bottle and then insert a cork into the neck, how could you remove the coin without taking out the cork or breaking the bottle?

How many pluses should we put between the digits of 987654321 to get a total of 99, and where?

Can you think of any three-dimensional shape that comprises of exactly two surfaces?

The first two letters signify a male, the first three letters signify a female, the first four letters signify a great, while the entire world signifies a great woman. What is the word?