Why is a river so rich ?

What does this rebus mean?

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TIME

How can you spell "White of an egg" in one word?
Hint: I know you can spell coke, poke, and joke.

Give it food and it will live; give it water and it will die.

What is the riddle which can be asked all day with a different correct answer each time.

There is a square of a particular number which when doubled, becomes 7 more than its quarter.

Can you find the number?

A man is surviving on an island along with his friend. They have been starving for four days for food. Suddenly, they find a fisherman. The friend goes with the fisherman in order to catch the fish (if they can find any).

The fisherman returns after some time but he is alone and has some salmon that he had prepared. When asked, the fisherman tells him that his best friend fell off the boat and drowned in the water. Starving for so long, he eats the meal while crying for his friend.

After being rescued, he goes to a diner and orders salmon. When he eats his meal, he jumps and commits suicide. Why did he do it?

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

On a magical land of Mexico , all the animal in the land are rational.

There are 10 tigers and one goat.
Tiger can eat goat but since it's a magical land , the tiger who eats the goat , turns into goat and then can be eaten by the remaining tiger(s).

If we leave them for some time then how many goat and tiger will be there , when we come back ?

It's a protector.
It sits on a bridge.
One individual can see directly through it, while others wonder what it hides.

What is it?