Sarah wanted to find out if heat had an effect on the growth of mold. She grew mold in nine jars. Each jar had the same amount and type of food. Three jars were kept at 0ºC. Three were kept at 90ºC. Three were kept at 27ºC. After four days she recorded the growth of the mold

This question is incomplete; but from the understanding of the question, it is about identifying the variables in the experiment e.g independent variable, dependent variable, control variable, control group etc.

The variables are as follows:

Independent variable: HEAT at different temperatures

Dependent variable: GROWTH OF MOLD

Constants/Control variables: Same amount of food, Same type of food

Control group: Jars kept at 0°C

Explanation:

A variable in an experiment are those factors that are subject to change. The INDEPENDENT VARIABLE in an experiment is that variable that is manipulated or controlled in order to bring about an outcome. In this Sarah's experiment, the independent variable is the HEAT CHANGE.

The DEPENDENT variable is the variable that responds to the changes made to the independent variable. The response of the dependent variable is dependent on the independent variable. In this experiment, the dependent variable is the GROWTH OF THE MOLDS because it responds to changes in heat (independent variable).

The CONSTANT or CONTROL variables in an experiment refers to the variables that are kept constant or unchanged throughout the experiment. Although they are not part of the experiment but they can affect the outcome of the experiment if changed. The constants in this experiment are the SAME AMOUNT and SAME TYPE OF FOOD given to each jar.

A CONTROL group is the group that does not receive any experimental treatment I.e. In this experiment, the jars placed at 0°C did not receive any heat, hence, they are the control group.

The experimental groups were the jars kept at 90°C and 27°C respectively.

i think a) betsy can donate only blood to mark is correct because, mark and betsy have the same blood type. whereas nobody else has b+ blood so betsy can't donate to them.

silt loam

hope this