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?

I have an eye but still cannot see.

Who am I?

A man who was outside in the rain without an umbrella or hat didn’t get a single hair on his head wet. Why?

Can you name four days which start with the letter 'T'?

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

I come in different shapes and sizes.
Parts of me are curved, other parts are straight.
You can put me anywhere you like,
but there is only one right place for me.
What am I?

A lion and its tamer are standing inside a cage that measures 1 unit in radius. Both of them can effortlessly run at the speed of 1 unit maximum.

1) Suppose the lion is hungry, will he be able to eat up the tamer?
2) If yes, how long can the tamer survive?

A dead body is found outside a multi-story multinational company. The case is reported and a homicide detective is called on the crime scene.

He looks at the body and then towards the building. From the position of the body, it is evident that the victim committed suicide. He goes to the first floor of the building and then walks in the direction of the dead body, opens the window and toss a coin in the air.

He goes to second floor and again repeats the process. He keeps doing this till he is done on all the floors. Then he returns back to the floor and tells his team that it is a murder.

How in heaven did he deduce that?

What goes up but never comes down?

Take one out and scratch my head, I am now black but once was red. What am I?