A 60-40 participation plan is in operation in a plant (base rate is guaranteed and operator receives 60 percent of proportional gain after exceeding 100 percent). The established time value on a certain job is 0.75 minute, and the base rate is $8.80. What is the direct labor cost per piece when operator efficiency is:
a. 50 percent of standard?
b. 80 percent of standard?
c. 100 percent of standard?
d. 120 percent of standard?
e. 160 percent of standard?