1. Professor Mary Beth Marrs took 6 hours to prepare the first lecture in a new course. Traditionally, she has experienced a 90% learning curve. How much time should it take her to prepare the 15th lecture?
2. The first vending machine that William Kine, Inc., assembled took 80 labor-hours. Estimate how long the fourth machine will require for each of the following learning rates:
a) 95%
b) 87%
c) 72%