1. why do scientists use the scientific method? to answer questions about the natural world to figure out how to run experiments to show people they are smart to collect data a student wants to determine the effect of a certain brand of liquid fertilizer on the growth of ivy. ivy plants of the same length are planted in the same amount of soil in three identical containers. to one container, 5 ml of the fertilizer is added; in the second container, 10 ml of the fertilizer is added; and in the third container no fertilizer is added. the containers are placed in front of the same window. the length of the ivy is measured every five days, and the observations are recorded in a data table. 2. what was the independent variable in this experiment? soil light fertilizer growth 3. list at least 1 control variable in the experiment. soil light fertilizer growth a scientist wants to determine if humidity affects chirping in crickets. she makes this table. 4. what is the independent variable? captionless image temperature humidty number of chirps 5. a scientist is testing the efficiency of various microwaves by measuring the temperature of water after being heated at high power for one minute. the temperature measured in this test is an example of independent variable dependent variable control group