What does this simple rebus mean?

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

If all the below statements are true

1. Gianni was either in Italy or France in 1997.
2. If Gianni did not kill Versace, Hilton must have killed him.
3. If Versace died of suffocation, then either Gianni killed him or Versace committed suicide.
4. If Gianni was in Italy in 1997, then Gianni did not kill Versace.
5. Versace died of suffocation, but he did not kill himself.

Who killed Versace and where was Gianni in 1997?

Can you find the key in the picture below?

A tree doubled in height each year until it reached its maximum height over the course of ten years. How many years did it take for the tree to reach half its maximum height?

Why is it very easy to weigh a fish?

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

Why do we preferably have round manhole covers and not square ones?

Using Only Five 5's and any mathematical operator make sum as 37

Find the next number in the series below.

6 18 270 72090 ?