Question

Questions 17 through 21 refer to the following passage: An experiment is designed to determine if wheat grows better when it is planted alone or with clover. The design calls for 3 pans of each treatment. Pans A, B, and C contain only wheat. Pans D, E, and F contain clover and wheat planted in alternating rows. Each pan contains a total of 100 seeds. All treatments contain the same type of soil, are planted in the same size pan, are exposed to the same amount of sunlight, and are maintained at the same temperature throughout the course of the experiment. Constants in this experiment are

A number of seeds in each pan, sunlight, one pan of wheat and clover.
B the pans in which wheat is alternated with clover.
C the pan of wheat, temperature, soil type.
D temperature, number of seeds in each pan, sunlight.
E soil type and sunlight.

Answer 1

Answer: D temperature, number of seeds in each pan, sunlight.

Constant means a situation that is not changed. In an experiment, a constant variable is any aspect of an experiment that is intentionally kept unchanged by the researcher throughout an experiment. There can be many constant variables n an experiment. In the example, .the number of seeds, the type of soil, the size of the pan, the amount of sunlight, and temperature are constant variables.