$(15$ points$)$ You decide that the additional cost from part g is not acceptable, so you consider quantity discounts, for which you have found a supplier. She will sell you the boxes at the following quantity discount pricing: $1$ to $9999$ boxes at $$0\mathrm{.}20$ per box; $10,000$ to $19,999$ boxes at $$0\mathrm{.}15$ per box; and $20,000$ and over at $$0\mathrm{.}10$ per box. What quantity will result in the least total cost? Use the same data from earlier in this problem. Show all work for partial credit. Zero points if only answers listed, even if correct. Proper methodology is required to earn any credit. If you use a spreadsheet, include the spreadsheet as a separate file.