What is the$$ long$-$run cost function if the production function is qequals$5$Lplus$3$K$?($Hint: In this$$ case, the two inputs are perfect substitutes in the production process$).$

Part $6$

The$$ long$-$run cost function is

Part $7$

A$.$

$$C$($q$)$equalswplusr$.$

B$.$

$$C$($q$)$equalsq$.$

C$.$

$$C$($q$)$equals$($w$/5)$q if $($w$/5)$greater than or equals$($r$/3),$ and $($r$/3)$q otherwise.

D$.$

$$C$($q$)$equals$($w$/5)$q if $($w$/5)$less than or equals$($r$/3),$ and $($r$/3)$q otherwise.

E$.$

$$C$($q$)$equalswq if wless than or equals$$r$,$ and rq otherwise.