Which number should replace the question mark?

In The 1st month of this year(the year 2013), I noticed that the date 13-1-13 (13 January 2013) is special.

This date is special as:

Date * Month = Year.

Can you figure out which year of this century has a maximum number of such dates?

There are 2 people near the river and both of them want to get on the other side. The boat can only take one of them. But they got across.
How?

What three numbers, none of which is zero, give the same result whether they’re added or multiplied?

There is a brick of gold and a brick of iron in a boat (both 10-inch blocks), if they are both dropped into the water which will make the water level higher?

What will you call your mother's brother's brother-in-law?

Move three sticks of the spiral below to form a square.

A Scientist was fifty years old in the year 2000 but he was forty years old in the year 2010. How can this be possible?

PS: It has a logical answer.

Can you convert the number zero(0) into a positive number using just one mathematical operator ?

You are given four results as below:
1111 = F
2222 = E
3333 = T
Then, can you find out how to code 4444?