given costC(x,y)=200000+5800x+4200y-100000e-0.01(x+y)  dollarsmarginal cost of a car:Cx(x,y)=0+5800(1)+4200(0)-100000e-0.01(x+y)((-0.01)(1+0))=>Cx(x,y)=0+5800+0+1000e-0.01(x+y)=>Cx(x,y)=5800+1000e-0.01(x+y) dollars marginal cost of ... See the full answer