What you cannot hold but it is yours?

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?

A Miser man decided to go on a vacation for a month. He goes to the bank and asks for a trip loan of $500. The bank officer asks the man that the loan can only be approved when he mortgage some valuable thing at the bank. Miser man mortgages his only car whose worth was a whopping $80000. The Bank officer laughed at him and approve the loan instantly. After vacation when the miser man returns, the bank officer asked him "Are you an idiot, why is your mortgage such an expensive car for such a short loan?".

Miser man replied with some reason and the bank officer agreed that the miser man is actually not an idiot.

What did miser man reply to the bank loan officer?.

The centre of the third figure is empty. What digit should fit inside?

How do you go from 98 to 720 using just one letter?

What does this below rebus puzzle mean?

A man and a dog were going down the street. The man rode, yet walked. What was the dog’s name?

What does below chemistry rebus means?

A man dies of old age on his 25 birthday. How is this possible?

Something Extraordinary happened on May 6th 19778 at 12:34am what was that?