7. (10 points) In some parts of the U.S., refillable glass bottles are still used extensively. A typical manual sorting area is 30 ft. long without room for expansion. Each sorter requires 3 ft. of space and stands on one side of a conveyor that runs along a wall. One sorter can't keep up with the flow, so additional workers can be added. (2 points) Complete the values of marginal product (MP) for L=4 and L=12. Total Product Marginal Product Labor (L) (TP or Q) of Labor (# Workers) (# Bottles) MPL O 0 N/A 1 5 5 2 18 13 3 36 18 4 56 520 5 75 19 90 15 98 8 104 6 108 4 10 110 11 2 110 12 0 108 13 - 2 104 b. (3 points) After which value of labor do marginal returns diminish? At value 8 4 came c. (3 points) Based on the inverse relationship between productivity and cost, what is the level of output where marginal cost is minimized? spot d. (2 points) For which range of labor does output increase at a decreasing rate? after L=4.. . up to when the number of workers =1 14