Use only one mathematical symbol and all numbers (0-9) to get a sum of 99

Lifeless eyes on my smiling face and watch your child's sleeping place. In their dreams they hold me tight. What am I?

Solve below popular number sequence
314 159 265 358 979 323 846 ?

Why do we preferably have round manhole covers and not square ones?

During which month do people sleep the least?

A mathematician couple was having a Frappuccino in Starbucks sitting opposite to each other. Suddenly the guy noticed the text written on the paper in front of them and exclaimed that it was wrong. The girl denied it and said it is appropriate. Both are correct. What is written on the paper?

Buy me, smell me or deliver me, I do not change.

Who am I?

What is in seasons, seconds, centuries and minutes but not in decades, years or days?

John was visiting his friend Jacob. He found out that his friend's wife had just killed a burglar in self-defense.
John asks Jacob about what happened and he told that "His wife was watching television when suddenly the bell rang. She thought that it is her husband Jacob but she found the burglar who attacked her instantly and she got so frightened that she killed the burglar immediately with the knife.
John asked the police to arrest his friend's wife. Why?

What does the below rebus riddle means?