Lucy plans to buy a refrigerator. She wants a large model so it has enough space for all the food she needs to store so that she
takes fewer trips to the grocery store. Lucy also wants a refrigerator that does not use too much electricity. However, when she goes to the appliance store, she finds that larger refrigerators use more energy. Which statement best explains why there is NO perfect solution for Lucy's a. Lucy cannot choose the values of the variables.
b. The two variables have to be calculated.
c. There is a trade-off between the two variables.
d. Lucy does not know which variable is more important.
