What has to be broken before you can use it?

What does the below rebus riddle means?

what does the below rebus means?

A train full of passengers goes through a tunnel. When the train comes out from the other end, there is no single person on the train.

How did it happen?

You see a boat filled with people, yet there isn’t a single person on board. How is that possible?

In a concert, Christina is performing a dance show with her group.
At 10:00, she and her crew were dancing in an absolutely straight line. At that time Christina was standing in 4th position from both the front and back end of the row.

What was the size of her crew?

You can hear me, but you can't touch or see me.

What am I?

Irene killed hundreds of people mercilessly and yet the police were not able to put her behind the bars. Why?

Can you guess the name of the month by looking the below rebus ?

Kohli and Dhoni decided to have a paintball match.
Kohli told Dhoni, "Sir it is not right as you got thrice the paintballs I have".

Dhoni instantly gives Kohli 10 hit paintballs.
Kohli replied, "Sir, I believe you still have twice the paintballs than I have".

Dhoni gives "?" more paintballs to Kohli.
Kohli replied, "Sir it is even now, Let us have a match".

What is "?".