A biology student wanted to determine if using fertilizer would promote plant growth. One hundred plants were randomly assigned to one of two groups: one that used the fertilizer, and one that did not use a fertilizer. Each plant was planted in the same amount of soil and given the same amount of water and light. Which of the following describes the benefit of using control in this experiment?

By controlling the amount of soil, water, and light in the experiment, we eliminate the need to have a control group.
By controlling the amount of soil, water, and light that may influence the response variable, we reduce variability in the response variable.
By controlling the amount of soil, water, and light that may influence the response variable, we eliminate variability in the response variable.
By controlling the amount of soil, water, and light, the differences observed in the response variable can be attributed to those variables that were controlled.

maybe showing the graph would

step-by-step explanation:

-387129 iq

its kind of blurry. can you put a clearer pic?

step-by-step explanation:

loloo

step-by-step explanation:

lololool

region b will make the inequalities y < 2x + 1 and y > -x - 2 true ⇒ answer a

step-by-step explanation:

* lets study the graph and the inequality to solve the question

- the inequality y > -x - 2

∵ the form of the inequality is y > mx + c , m is the slope of the line

  and c is the y-intercept (the line intersect y-axis at point (0 , c)

∴ c = -2 that means the line intersect the y-axis at point (0 , -2)

∵ the sign of the inequality is >

∴ we shad the part over the line

  region a and b

- the inequality y < 2x + 1

∵ the form of the inequality is y > mx + c , m is the slope of the line

  and c is the y-intercept (the line intersect y-axis at point (0 , c)

∴ c = 1 that means the line intersect the y-axis at point (0 , 1)

∵ the sign of the inequality is <

∴ we shad the part under the line

  region b and c

∵ the common region between the two lines is region b

∴ region b will make the inequalities y < 2x + 1 and y > -x - 2 true