Capital Candy Company sells boxes of assorted candies, which it purchases from its suppliers for $$4\mathrm{.}50$ per unit. Sales vary throughout the year, but to ensure it always has stock on hand, it has a policy of requiring an ending inventory for any period to be large enough to cover $20\%$ of the next period's demand. Budgeted sales $($in units$)$ for the year ended December $31,20$X$1$ are as follows:

$Q1-13,600$

$Q2-6,700$

$3-15,200$

$Q4-17,800$

Assuming that inventory on hand at the beginning of each period matches that planned for in the policy above, what would be the cost of purchases for Q$3?$

a$.$ $$70,740$

b$.$ $$98,100$

c$.$ $$29,700$

d$.$ $$84,420$