Problem 1
The price per unit of a certain product is p=50-0.2x where x is the number of units sold. The revenue obtained by selling 90 units of the product is:
A: 2460
B: 2720
C: 2880
D: 3120

Problem 2
The price per unit of a certain product is p=50-0.2x where x is the number of units sold. The total cost of producing x units of the same product is TC(x) = 1000+10x. The profit obtained by producing and selling x units is:
A: π(x) = -0.2x² + 40x-1000
B: π(x) = -0.2x² +40x+1000
C: π(x) = -0.2x² +48x-1000
D: π(x) = -0.2x² +48x+1000


Problem 3
The price per unit of a certain product is p=50-0.2x where x is the number of units sold. The total cost of producing x units of the same product is TC(x) = 1000+10x. The price that maximises the profit is:
A: p = 15
B: p = 20
C: p = 25
D: p = 30


Please send full explanation