Concept:The given supply equation P=0.3Q directly gives the price P for any quantity Q.Explanation:The supply function is P=0.3Q.Here, P represents the price in dollars and Q represents the quantity of mangoes supplied.We are asked to find the price when Q=50.Substitute Q=50 into the equation:P=0.3×50Multiply:0.3×50=15Thus, the price is P=15 dollars.The units are dollars, so the price is $15.00.This matches option D.Answer:The price P when Q=50 is $15.00.Correct option: D. $15.00.