The area is 270 inches, because you would do length times width, which in this situation is 28 and 15. You multiply them, and you get 270.
It sucks that points have to be used in order to post questions.
Openstudy - the company that merged into Brainly - was much better.
Anyway, I think that the answer to this question is A. I'm not sure, though.
Answer:
He did not control for lurking variables and their impacts on the results of his experiment. Amount of sunlight and water received are two outside variables(or confounding variables) that may impact the growth of his plants and influence the results. He needs to apply the same amount of sunlight and water to each plant within a different planting soil in order to rule out the influence of those two variables and test the sole effect of the soil brand on the plant growth. Otherwise, it would be hard to determine whether his plant growth was because of the soil brand or the different amounts of sunlight and water received
