A Regression Analysis Between Demand (Y in 1000 Units) and Price

A regression analysis between demand (y in 1000 units) and price (x in dollars) resulted in the following equation: ? $\hat {y }$ = 9 ? 3x
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The above equation implies that if the price is increased by $1, the demand is expected to _____.

A) increase by 6 units
B) decrease by 3 units
C) decrease by 6,000 units
D) decrease by 3,000 units