The data below shows the weight gain by white rats over the same period where each group was given a different type of bread for food.

Rye Bread: 12, 14, 13, 15, 19, 17, 15
Whole Wheat Bread: 10, 15, 13, 19, 19, 14, 15

A. What are the independent and dependent variables?
B. Calculate the means of both groups?
C. Does there appear to be a difference in task performance between the two groups? Explain.