Under Learning Curve Theory,with a Learning Rate of 70 Percent

Under learning curve theory,with a learning rate of 70 percent

A) the time to produce the second unit will be 70 percent less than the time to produce the first unit.
B) the time to produce the second unit will be 30 percent less than the time to produce the first unit.
C) the cumulative average time per unit after producing the first 100 units will be 70 percent less than the average time per unit of the first 50 units.
D) the average time per unit will be cut in half for every 70 units.