It is a Compound.
Water can't be a mixture because it is chemically bonded and cannot be separated into H2 and O by physical means.
And water cannot be an element, because it is made of atoms of different types [H and Oxygen]
Rust is iron oxide, the corrosion product of iron when exposed to the oxygen in the air. Tin is not iron, so you cannot produce iron oxide from the corrosion of tin. Because the layer of tin on the surface of the steel prevents atmospheric oxygen and moisture from contacting the steel.
A b and e is are the answers
The answer would be B. Increased fertility downstream. Hope this helps. It's been a while since iv'e done the test, but I think this is the correct answer.
