It has been argued that like books and stories, television not only entertains, it also exposes a child to new information about the world. While watching too much television is harmful, a little bit may actually help. The accompanying data file contains information on the grade point average (GPA) of 28 middle school children and the number of hours of television they watched per week.

Click here for the Excel Data File

Estimate a quadratic regression model where the GPA of middle school children is regressed on hours and hours-squared.

Note: Negative values should be indicated by a minus sign. Round your answers to 2 decimal places.

predictor variable	coefficient
constant
hours
hours-squared

Is the quadratic term in this model justified?

1. multiple choice

Find the optimal number of weekly hours of TV for middle school children.

Note: Round intermediate calculations to at least 4 decimal places and final answer to 2 decimal places.

No, because the estimated coefficient for Hours is not statistically significant at the 5% level.

Yes, because the estimated coefficient for Hours is statistically significant at the 5% level.

No, because estimated coefficient for Hours-squared is not statistically significant at the 5% level.

Yes, because estimated coefficient for Hours-squared is statistically significant at the 5% level.

Find the optimal number of weekly hours of TV for middle school children.

Note: Round intermediate calculations to at least 4 decimal places and final answer to 2 decimal places.

GPA	Hours
3.24	19
2.86	21
3.24	18
2.61	30
3.03	23
3.37	10
1.6	36
3.2	10
2.96	13
2.18	31
2.5	33
2.95	4
2.72	25
3.05	21
3.45	8
2.49	27
3.62	11
2.33	29
2.36	30
3.28	10
3.35	15
2.64	18
2.88	24
2.02	29
2.6	22
3.18	21
3.31	4