(Table: Barbara's Production Function for Hockey Jerseys) Use Table: Barbara's Production Function for Hockey Jerseys. Diminishing returns to labor begin to kick in after Barbara hires the ______ worker.
Table: Barbara's Production Function for Hockey Jerseys Number of Sewing Machines Number of Hockey Jerseys 0 0 1 75
2 150 3 250 4 325 5 375 a. Second b. third c. fourth d. fifth