I am lying and I always lie. Tell me whether I am lying or telling the truth.

Is the statement valid that it does not matter how much older a sibling is, eventually the younger one will be half as old as the older one?

Below toothpicks/matchsticks indicate the group of fishes moving from west to east direction. Can you make them move from east to west by just moving three toothpicks/matchsticks?

I am an eight letter word and I am a computer terminology.
The second, third and fourth letters make an animal.
The fourth, fifth, sixth, seventh and eighth letters make a weapon.
The first, second, third and fourth letters can be taken as an outcome of any exam.
The fifth, sixth, seventh and eighth letter combine to form a high end typing software.

Can you tell who am I ?

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

If eleven plus two equals one, what does nine plus five equal?

Why is the longest human nose just 11 inches?

Until it is measured, not known. Yet how you miss it when it has gone. What is it?

What is next number in the pattern below:

131 517 192 123 ?

What has no start, end, or centre?