How can you make number one disappear by adding something to it?

Can you find out the smallest number that can be conveyed as the sum of three squares in three unique ways?

There was an aeroplane crash, every single person died, but two people survived. How is this possible?

It comprises roots which nobody sees,
Much taller than those trees,
Up and up it goes,
Still it never grows?

You walk into a room where there are three primates held in their respective cages:
1) A lion who is eating the flesh of a goat.
2) An orangutan who is playing with blocks.
3) A donkey who is sitting idle.

Who is the most intelligent primate in the room?

I came first on earth but second on the heaven.
I also came twice in a week but found just once in a year.
I stay away from months but you can find me in February.

What am I?

Replace the letters of words with a number so that the below equation holds true

BASE +
BALL
---------
GAMES
----------

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.

In the below-given picture of a pretty girl, there is something wrong. Can you find out what it is?

Make eight squares by moving only two matchsticks.
Note- Square can be of different sizes.