Exhibit 13-12
in a Laboratory Experiment, Data Were Gathered on the Life

question 127

Multiple Choice

Exhibit 13-12
In a laboratory experiment, data were gathered on the life span Y in months) of 33 rats, units of daily protein intake X1) , and whether or not agent X2 a proposed life extending agent) was added to the rats diet X2 = 0 if agent X2 was not added, and X2 = 1 if agent was added.) From the results of the experiment, the following regression model was developed.
$\hat { Y }$ =36+0.8X1 - 1.7X2
Also provided are SSR = 60 and SST = 180.
-Refer to Exhibit 13-12. The degrees of freedom associated with SSE are

• A) 3
• B) 33
• C) 32
• D) 30