the ABC marketing consulting firm found that a particular brand pf portable stereo has the following demand curve for a certain region: Q=10,000 - 200 P + 0,03 Pop + 0, 6 I + 0.2 A where is Q the quantity per month, P is price ($), Pop is population, I is disposable income per household(S), and A is advertising expenditure($). a.determine the demand curve for the company in a market in which P=300, Pop= 1,000,000, I=30,000, and A=15,000 b. calculate the quantity demanded at prices of $200, $175, $150, and $125. c. calculate the price necessary to sell 45,000 units