Can i get someone to me with this problem

Problem/Question: There are many snowy days, but salt can potentially harm vegetation near the roadways

Possible Hypotheses: If we use other, but healthier chemicals less harm will be put upon the vegetation.

Manipulated/Independent: Amount of chemicals we use/which chemical we use

Responding/Dependent: Vegetation

Constants (list three):

-amount of knew salt

-amount of snow

-area of which the experiment is tested in

Control: The salt before the change in chemical

definition was not one of the four methods