Answer:
Step-by-step explanation:
Given
Company Produces and sells 211600 boxes of T-shirt each year
Fixed cost =$ 400
Additional cost = $ 3 per box
storage cost =$ 2
let x be the no of production run
therefore
Holding cost per year 

yearly ordering cost
Total cost C(x)
differentiate C(x) w.r.t to x we get

Put
to get max/min value




therefore 46 runs must be performed
There is only 1 real number solution
Well, from what you’ve posted, it seems that a negative value cannot be accepted since that would imply she has gone underwater. She also cannot go above 300 feet since she is going downwards from a max height.