Aresearcher finds that white bread contains more preservatives and has a higher moisture content than wheat bread. she designs a test to determine whether the type of bread, white or wheat, affects the amount of mold growth. what must be done for the researcher to accurately measure the dependent variable? she will need to allow mold to grow for more days on the white bread, since it contains more preservatives, to measure the dependent variable. she will need to limit the dependent variable to white bread or wheat bread. she will need to allow mold to grow for fewer days on the white bread, since it contains more preservatives, to measure the dependent variable. she will need to learn out how to quantitatively measure mold growth to measure the dependent variable.

She will need to learn out how to quantitatively measure mold growth to measure the dependent variable.

Explanation:

The independent variable is the variable which can be altered in an experiment so as to observe it's effect over the dependent variable. The dependent variable is the one which cannot be manually altered in an experiment instead the changes occurring on them is because of the independent variable. It is the outcome of the experiment.

Here, in the experiment preservatives and moisture content are the independent variables. But the researcher is required to measure the amount of mold grown over the surface of the bread. This will be the outcome of the experiment.

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