How can a man go eight days without sleep?

What does the below rebus riddle means?

I was speeding and ran through a stop sign, yet two traffic officers who were there do nothing about it.

why?

When you say goodbye, I am what you need to tie.
I come as a couple and go wherever you run.
Who am I?

There was once a college that offered a class on probability applied to the real world. The class was relatively easy, but there was a catch. There were no homework assignments or tests, but there was a final exam that would have only one question on it. When everyone received the test paper it was a blank sheet of paper with a solitary question on it: 'What is the risk?'.Most students were able to pass, but only one student received 100% for the class! Even stranger was that he only wrote down one word!
What did he write?

Can you spot the hidden girl in the picture below?

Which Burger Is Different in below image?

What 5-letter word typed in all capital letters can be read the same upside down?

If it took eight men ten hours to build a wall, how long would it take four men to build it?

John drives to his office at 20km/hr. After reaching the office, he realizes that today is a holiday. He went back at an average speed of 30km/hr. Discounting the time spent in the stoppage what was the average speed of his journey?