Consider the following cost$$ function:

Upper C equals $0\mathrm{.}3$ q cubed minus $3$ q squared plus $80$ q plus $100$C$=0\mathrm{.}3$q$33$q$2+80$q$+100.$

Part $2$

When output is $12$units$,$ average cost is $$$$95\mathrm{.}53$units, marginal cost LOADING... is $$$$137\mathrm{.}6137\mathrm{.}6.$

Part $4$

The output level where average variable cost LOADING... equals marginal cost is