Question

ten plants are grown in equal amounts of sunlight with equal amounts of water and varying amounts of fertilizer. sunlight, water, and fertilizer are

systems.

experiments.

controls.

variables.

question 6
an experiment was designed to measure the effect of sulfur dioxide emissions from a power plant on the ph of rain falling downwind of the plant. in this experiment, the average ph of rainwater from the plant would be considered

Explanation:

In an experiment, variables are factors that can change. Here, sunlight, water, and fertilizer are factors affecting plant growth (fertilizer varies, others are controlled but still variables). Systems are complex entities, experiments are the whole procedure, and controls are kept constant. So they are variables.

Answer:

D. variables