Can you solve below mathematical equation?

2^1234 - 2^1233

What number does the below three word/phrase identify and why?
1. Deck
2. Year
3. Singing in the Rain

Who has married many women but was never married?

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?

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 ?

You need to arrange three 7 and mathematical symbols to form number 1?

You bought me for dinner but never eat me. What am I?

Which point will the car reach to go out?

What has many keys but can’t open a single lock?

A man walked into a pub and went straight towards the Barman. He asked for a dirty martini from the Barman. The Barman thought something and then pulled out a pistol from his drawer and aimed it directly at the man. Why did he do that?