What has 13 hearts but no other organs?

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 ?

In the given figure, move three matchsticks so that the resulting figure contains two rectangles.

There are 2 people near the river and both of them want to get on the other side. The boat can only take one of them. But they got across.
How?

Most people think of me as money. But when they find me in the water, they won’t get any money out of me. What am I?

It has a long neck, A name of a bird, Feeds on cargo of ships, It's not alive,

What is it?

What does this say?

XLR8

I am something people love or hate. I change peoples appearances and thoughts. If a person takes care of them self I will go up even higher. To some people I will fool them. To others I am a mystery. Some people might want to try and hide me but I will show. No matter how hard people try I will Never go down. What am I?

The doctor advised his patient to take a tablet after every fifteen minutes. He gave him five tablets in total.

How much time will he take to have all the five tablets?

What does does this rebus picture means ?