You Have Just Timed a Person Doing a Job a Four

Multiple Choice

You have just timed a person doing a job a four times.The first time it took the person 120 minutes,the second time it took 90 minutes,the third time it took 76.1 minutes and the fourth time it took 67.5 minutes.Which Learning Curve Unit Improvement Factor should you use?

A) 25 percent
B) 75 percent
C) 80 percent
D) 85 percent
E) 90 percent