A man dies of old age on his 25 birthday. How is this possible?

Remove two matchsticks to make the below equation correct.

I never stop running even when I standstill. If I am formed by joining two identical bodies together, can you guess who I am?

Christina has four daughters, and each of her daughters has a brother. How many children does Christina have?

Can you make a six-letter word using the letters N, A and B ?

A man looks at a painting in a museum and says, “Brothers and sisters I have none, but that man’s father is my father’s son.” Who is in the painting?

Living above a star, I do not burn
Eleven friends and they do not turn
I can just be visited in a sequence, not once or repeatedly
PQRS are my initials
Can you tell my name accurately?

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?

In front of you, there are 9 coins. They all look absolutely identical, but one of the coins is fake. However, you know that the fake coin is lighter than the rest, and in front of you is a balance scale. What is the least number of weightings you can use to find the counterfeit coin?

Prove that the below maths equation is true.

8 + 8 = 91