A student wants to answer the question “Does adding calcium powder to soil make pea plants grow faster?” She adds calcium powder to the soil of 12 plants and does not add it to the soil of a second group of 12 plants. She measures the growth of all of the plants in each group for a month. Which statement best summarizes the factors that need to be controlled in this experiment?

Respuesta :

Nouri
Hi there!

We can determine what the dependent and independent variables are in this experiment so that we can narrow down what factors need to be constant.

Dependent variable - Growth of the plants
Independent variable(s) - Calcium powder

The control variable are the constant variables in an experiment kept constant to ensure the results of the experiment are valid. Therefore, in this experiment the control variables are...

Control variables - Amount of water, sunlight, type of pea plant, mode of measuring the growth

Answer: A.)  All plants should be the same age and health and be given equal amounts of water and sunlight.

Explanation:

Just took the test