What word does this rebus represent?

meta meta
meta meta

What has many teeth, but cannot bite?

Three friends decide to distribute the soda cans they had among them. When all of them had drunk four cans each, the total number of cans that remained was equal to the cans each one of them had after they had divided the cans.

Can you calculate the total number of cans before distribution?

It can't be seen, can't be felt, can't be heard, and can't be smelt.
It lies behind stars and under hills, And empty holes it fills.
It comes first and follows after, Ends life, and kills laughter.
What is it?

What mathematical symbol can be put between 5 and 9, to get a number bigger than 5 and smaller than 9?

Here is a mathematical expression that also secretly tells a movie name. What movie is that?

Forwards I am heavy, backward I am not. What am I?

A bomb exploded in a room full of married couples and no one died. How?

You need to complete the maze by entering from the entrance marked below in the figure near the yellow circle, bottom left and leaving from the exit point near the green circle, bottom middle.

Rule of Game: You can move only by exchanging green and yellow circles.

In 1990, a person is 15 years old. In 1995, that same person is 10 years old. How can this be?