Question

Review a fertilizer company has created a new formula for its fertilizer that its scientists think will work better than tfrie original formula, but the new fertilizer has more expensive chemicals in it. They decide to test their new fertilizer against the old fertilizer . They plant 90 quadrants or grass. On 30 they put the new fertilizer, on another 30 they put the old fertilizer , and on the other 30 they use no fertilizer. They plant the same type of grass seeds on all 90 quadrants, wait two weeks and measure the average grass height on all 90 plots. They compare the three groups to each other. 1. What is the independent variable in this experiment? 2. What is the dependent variable in this experiment? 3. What is the control group in this experiment. 4. Why is it necessary to have a control group?

Answer 1

Answer:

The correct answer will be-

1. independent variable- the type of fertilizer

2. dependent variable- height of the plants

3. control group- The quadrant without any fertilizer treatment

4. Importance of control group- acts as reference to the experimental group as is performed without the key component in natural conditions.

Explanation:

A scientific experiment contains three types of variable and is divided into two types of group of samples.

The variables studied in the experiment are;

1. Independent variable: parameter which changes or is induced to change as per the demand of the experiment like the type of fertilizer in the experiment.  

2. Dependent variable: parameter which depends on the independent variable and has to be studied in the experiment like the height or growth of the plant.

3. Control group: the group of samples left untreated in which the key component like fertilizer is not provided. So, the quadrant without any fertilizer treatment will be considered the control group.