The answer to that question is c
Explanation:
The most reactive metals are found on the left of the periodic table, in the blue column, known as the alkali metals. Their reactivity increases as we go down column (group) one. Reactive metals, when attached to less reactive metals, have the ability to prevent the less reactive metal from rusting.
Of any substance? What about two powders such as 1/2 cup of white flour, then mixing 1/2 cup of salt together with the flour. This would then form a more coarse mixture being that the two particles differ in shape.
Answer: Depending on the state of change it can be a physical change. Example: Evaporation is the physical change of a liquid turned into a gas.
That said, I'm pretty sure the answer is (True)
Note: Hope this is correct and it helps. Good luck :)