Check Your Understanding: 1. Do homes with metal roofs get worse cell service than homes with shingled roofs? Ben and Jerry are neighbors and own an ice cream business together. Ben has a metal roof on his home and Jerry has a shingled roof. Ben and Jerry select a random sample of 50 employees. They randomly assign them to come to a party at either Ben's house or Jerry's house. When they arrive Ben and Jerry ask them about their signal strength. Was this an observational study or an experiment? Justify your answer. 2. A study showed that one factor that strongly correlates with student academic success is the number of books that the family has in their home. Researchers randomly selected 100 students and measured their academic success as well as counted the number of books their family has in their home. a. Is this an observational study or an experiment? Justify your answer I b. What are the explanatory and response variables? c. Explain clearly why such a study cannot establish a cause-and-effect relationship. Suggest a variable that may be confounded with number of books that the family have in their home.