Complete the table series riddle by finding the number that can replace "??".

Cristina was born in 1888. She just had her 30th birthday today how did that happen?

There are nine dots in the picture that has been attached with this question. Can you join all the dots by drawing four straight lines without picking up your pen?

Can you count the number of blocks in the picture below?

Railroad Crossing, look out for the cars. Can you spell that, without any R's ?

There are 20 people in an empty, square room. Each person has full sight of the entire room and everyone in it without turning his head or body, or moving in any way (other than the eyes). Where can you place an apple so that all but one person can see it?

What can you see in the middle of March and April that you can never see in any other month?

Vin Diesel is pulling a theft and has planned to run away with all the cash kept in the safe. But the only way to open the safe is the 13 character password. He has a set of five clues given to him by a trustworthy source.

Exactly two of the below statements are false.
The password is contained within this sentence.
The password is not in this hint.
The password is within only one of these statements.
At least one of the above statements is a lie.

What always comes into a house through the keyhole?

Can you decipher the below rebus?

PBLUESAISNUERSES