For part a) of this question, I calculated the total batches to be 1,2,4,8,16, the average time per batch to be 200,176,154.88,136.2944, total time for total number of batches to be 200,352,619.52,1090.355, and total labour costs to be 2400,4224,7434.24,13084.26,26168.52.
The answers that I have calculated seem to be wrong
The question asks for the total labour costs for each of the 5 months.
You have calculated the total cost of June, but then for June + July, for June + July + August, etc., which is not what the question required. It wants the cost for each of June. July, August etc. separately.