How to compute the cost of a Cloud ML job?

Question

My Cloud ML training job completed with the output:

"consumedMLUnits": 43.24

How do I use this information to determine the cost of the training job? I can't decide between the following two options:

1) According to this page, I should multiply $0.49 (since I am located in the US) by the number of ML units by the duration of the job (which was 4.5 hours). So:

$0.49 x 43.24 x 4.5 = $95.3442

2) On the other hand, my experience has been that longer running training jobs lead to higher values for consumedMLUnits, which suggests to me that duration has already been incorporated into this metric. If so I think the calculation would be:

$0.49 x 43.24 = $21.1876

Which of these is correct?

Answer 1

2) is correct - duration has already been incorporated into this metric, hence the correct calculation is:

$0.49 x 43.24 = $21.1876