Solution:
The principle of the learning curve shows that the period to perform a task is multiplied by a set number.
With this question, we generated the second unit,
So that we can approximate the percentage of learning from the first unit
= (Unit 2 time)/(Unit 1 time)
= 11/13
= 0.84 ≅ 1
1 Unit would be the estimate of the learning percentage in this process