The First Unit of a Product Took 50 Hours to Build,and

Multiple Choice

The first unit of a product took 50 hours to build,and the learning curve is 85%.How long will it take to make the 10th unit? (Use at least three decimals in the exponent if you use the formula approach. )

A) less than 24 hours
B) from 25 to 30 hours
C) from 30 to 35 hours
D) from 35 to 40 hours
E) more than 40 hours