statistics economic

The below is the regression output that explains sales in terms of price and advert. The regression is linear where sales = b1 + b2*price + b3*advert. Use alpha = 0.05, critical t-value = 1.99, n = 75. Coefficients: Estimate Std. Error Intercept) 118.91 6.35 price -7.91 1.10 advert 1.86 0.68 If the price decreases by 1 unit and advert increases by 1 unit, then sales will change by