Answer:
A. 49 hours
Step-by-step explanation:
Unit: 1 2 4 8
Time: 10 hours 7 hours
Total Time: 10 hours 17 hours divided by 2
Average: 10 hours 8.5 (85% learning curve) 8.8 x .85 = 7.225 7.225 x .85 = 6.141
So total time taken by 8 rings will be 6.141 x 8 = 49.13 hours.