What does this mathematical rebus means ?

What word does this rebus represent?

meta meta
meta meta

What does below science rebus mean?

Ag Ag Ag
Ag SPOON Ag
Ag Ag Ag

If 5 cats catch 5 mice in 5 minutes, how long will it take one cat to catch a mouse?

When I go in I might cause pain. I cause you to spit and ask you not to swallow. I can fill your hole. What am I?

French Police inspects a room where there are no windows, no doors, no tables and is almost empty expect there is just a puddle of water. They found a dead man who obviously hung herself from the ceiling, but they are not able to figure out how this had happened.

John and Jacob entered the crime scene and easily able to solve the case.

How did the man die?

I sleep during the day and fly at night, but I have no feathers to aid my flight. What am I?

Can you find a pattern and the missing number in the series given below?

100, 155, 258,? , 584, 819.

I cry without having a voice.
I fly without having wings.
I bite without having teeth.
I whisper without a mouth.

Who am I?

What is common among 11, 69, and 88?