Can you solve below mathematical equation?

2^1234 - 2^1233

An express train takes 3 seconds to enter the tunnel which is 1 km long.
If it is travelling at 120 km an hour, how long will it take to pass completely through the tunnel?

How many triangles are there in the picture below?

I am a white box having no key or lid.
Yet there is a golden treasure inside it.

What Am I?

I am written with two letters.
I said with the one.
I usually am seen with the two.

Who am I?

A clock loses 10 minutes each hour. If the clock is set correctly at noon, what time is it when it reads 3 PM?

What does below Rebus mean ?

esgg sgeg gegs gsge

I am not a bull but I have horns.
I am not an ass but I have a pack saddle.
Wherever I go, I leave silver behind me.

Who am I?

The person who makes it has no need for it. He who purchases it does not use it. The person who does use it does not know they are. What is it?

How old is your son? asked a man to his neighbour. My son is five times as old as my daughter and my wife is five times as old as my son. I am twice as old as my wife whereas my grandmother, who is celebrating her eighty-first birthday is as old as all of us put together.

How old is the man's son ?