A regression model between sales (yin $1000), unit price (x₁in dollars), and television advertisement (x₂in dollars) resulted in the following function:

= 7 - 3x₁+ 5x₂

For this model, SSR = 3500, SSE = 1500, and the sample size is 18.At the 5% level,

a. it can be concluded that the model is significant.

b. there is evidence that the slope of x₂ is significant.

c. the conclusion is that the slope of x₁ is significant.

d. there is no evidence that the model is significant.