Answer:
A) 90%
Step-by-step explanation:
We know that by the learning curve, as cumulative output doubles the cumulative average time taken per unit decreases by a constant percent and the constant percent is the learning rate.
We need to double output 2 times in order to get from 1 to 4, so, we get the following:
[tex]10*n^2=8.1\\n^2=0.81\\n=0.9=90%[/tex]
The conclusion is that the learning curve for this operation is 90%.