1. In 2009, the New York Yankees won 103 baseball games during the regular season. The table below lists the number of victories (W), the earned run-average (ERA), and the batting average (BA) of each team in the American League. The ERA is one measure of the effectiveness of the pitching staff, and a lower number is better. The batting average is one measure of effectiveness of the hitters, and a higher number is better.

Team	W	ERA	BA
Yankees	103	4.26	0.283
Angels	97	4.45	0.285
Red Sox	95	4.35	0.270
Twins	87	4.5	0.274
Rangers	87	4.38	0.260
Tiger	86	4.29	0.260
Marines	85	3.87	0.258
Rays	84	4.33	0.263
White Sox	79	4.14	0.258
Blue jay	75	4.47	0.266
Athletics	75	4.26	0.262
Indians	65	5.06	0.264
Royal	65	4.83	0.259
Orioles	64	5.15	0.268

1. Develop a regression model that could be used to predict the number of victories based on the ERA.
2. Develop a regression model that could be used to predict the number of victories based on the BA.
3. Calculate the values of r for both models and interpret the value of r in the context of this problem
4. Which of the two models is better for predicting the number of victories?
5. Should both variables be included in the model? Why or why not?