Answer: a) y = 10x +500 b) $500 c) $15 for 100; $10.50 for 1000Step-by-step explanation:a)We assume the given "cost per unit" is the variable cost per unit. The total cost (y) for x units, given some fixed cost (b), is ... y = 10x +bFor 100 units, this is ... 1500 = 10(100) +b 500 = b . . . . . . . . subtract 1000The cost function rule is ... y = 10x +500__b)The fixed cost is the cost of producing 0 units: y = 10(0) +500 y = 500 . . . . . . . the fixed cost in dollars__c)The average cost (ac) of producing n units is the total cost divided by n: ac(n) = (10n +500)/n = 10 +500/nThe average cost for 100 units is ac(100) = 10 +500/100 = 15 . . . average dollar cost for 100 unitsThe average cost for 1000 units is ... ac(1000) = 10 +500/1000 = 10.50 . . . average dollar cost for 1000 units