Two in a corner, one in a room, zero in a house, but one in a shelter. What is it?

I am a white box having no key or lid.
Yet there is a golden treasure inside it.

What Am I?

A rubber ball keeps on bouncing back to 2/3 of the height from which it is dropped. Can you calculate the fraction of its original height that the ball will bounce after it is dropped and it has bounced four times without any hindrance ?

I can write cow in 13 letters.

Can You?

It is an eleven letter word.
The first, second, third and fourth letters form a banquet's name.
The fifth, sixth and seventh letters form a car's name.
The eighth, ninth, tenth and eleventh letters form a mode of transport.

Can you identify what word it is?

Can you find out the remainder when 3^300 is divided by 5?

When it's bad luck to meet a black cat?

A seven-year-old kid challenged his classmates that he can make the number one disappear by adding something to it.

How can he do that?

Identify the hidden meaning behind this picture?

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 ?