The question: How would I answer these questions using SpSS?

Read the description below: Kyler, the local dogcatcher, predicts that dogs at the pound will bark less when they are fed expensive name-brand food than when they are fed a cheaper generic brand of dog food. To test his hypothesis, he feeds one group of dogs the expensive brand name food for 1 week and records the number of barks during the 1-hour period following each feeding. The next week, he feeds an entirely different group of dogs the cheaper generic brand food for 1 week and records the number of barks during the 1-hour period following each feeding. The data for the dogs follow. Page 2 of 4 Number of Barks Expensive Brand Name Food 123 Cheap Generic Brand Food 145 100 128 165 138 154 136 169 125 198 136 127 111 145 156 154 139 136 128 129 129 106 1282. a. What is the independent variable? b. What are the levels of the independent variable? c. What is the dependent variable? d. Is the research hypothesis one tailed or two tailed