What does below science rebus mean?

Ag Ag Ag
Ag SPOON Ag
Ag Ag Ag

What does this rebus mean?

O
N
C
E
TIME

People put me on the table and cut me but do not eat me. What am I?

Vin Diesel is pulling a theft and has planned to run away with all the cash kept in the safe. But the only way to open the safe is the 13 character password. He has a set of five clues given to him by a trustworthy source.

Exactly two of the below statements are false.
The password is contained within this sentence.
The password is not in this hint.
The password is within only one of these statements.
At least one of the above statements is a lie.

Can you write down eight eights so that they add up to one thousand?

Why Aeroplane windows are round?

Consider this about a word: The first two letters signify a male, the first three letters signify a female, the first four letters signify a great, while the entire world signifies a great woman. What is the word?

Mr Black, Mr Gray, and Mr White are fighting in a truel. They each get a gun and take turns shooting at each other until only one person is left. Mr Black, who hits his shot 1/3 of the time, gets to shoot first. Mr Gray, who hits his shot 2/3 of the time, gets to shoot next, assuming he is still alive. Mr White, who hits his shot all the time, shoots next, assuming he is also alive. The cycle repeats. If you are Mr Black, where should you shoot first for the highest chance of survival?

John’s parents have three sons: Snap, Crackle, and what’s the name of the third son?

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