Just need help with question 9!! Question 4 is there for reference.

Based on the same structure as 4a: What would be the price of the output in the long run? For each of the following production functions and quantity wished to produce, given a fixed capital amount equal to 1 , what is the amount of labor that minimizes costs? (Answer as a whole number, no decimals included; if impossible, answer NA) A) q=K+L,10 B) q=min{20K,10L},10 : C) q=min{20K,10L},40 : D) q=K0.5L0.5,10