What does this rebus riddle means ?

What is the longest word in the dictionary?

A girl was sitting in her hotel room when she heard a knock on the door. She opened the door and found that a man was standing outside. The man said, "Oh! I am really sorry, I thought this was my room." He then walked through the corridor to the elevator. The girl did not know the man. She closed her door and called security asking them to apprehend the man. What made her suspicious of that man? He might have been genuinely mistaken.

You can find some missing letters in the picture. By placing two particular letters in the spaces, you can form a nine lettered word beginning from one of the corners and going clockwise direction to the middle. Can you find out the letters and the word?

Which is faster, Heat or Cold ? Explain.

Replace the question mark with the correct number.

There are 2 cops parked along a one-way street looking for traffic violations. They spot a taxi driver going in the wrong direction, yet they do nothing.

Why?

What does this mean?

CCCCCCC

Can you solve below mathematical equation?

2^1234 - 2^1233

What does the below image rebus riddle means ?