Independent Variable is what you change in an experiment. A Dependent Variable is what you’re trying to find out. Constants are what you keep that same. Control Group is the standards to which comparisons are made.
We need the options in order to answer
Preformed water (ingested in food and drink) and metabolic water (by product of aerobic respiration and dehydration synthesis)
You need larger amounts of macrominerals. They include calcium, phosphorus, magnesium, sodium, potassium, chloride and sulfur. You only need small amounts of trace minerals.
I believe it’s cover crops but i could be wrong hope it helps