A Regression Model Between Sales (Y in $1000), Unit Price

Multiple Choice

A regression model between sales (y in $1000) , unit price (x₁ in dollars) , and television advertisement (x₂ in dollars) resulted in the following function: ​ = 8 - 4x₁ + 5x₂
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For this model, SSR = 3500, SSE = 1500, and the sample size is 20. The coefficient of the unit price indicates that if the unit price is

A) increased by $1 (holding advertisement constant) , sales are expected to increase by $4.
B) decreased by $1 (holding advertisement constant) , sales are expected to decrease by $4.
C) increased by $1 (holding advertisement constant) , sales are expected to increase by $4000.
D) increased by $1 (holding advertisement constant) , sales are expected to decrease by $4000.