Gazu Ltd manufactures fiberglass surfboards. One of the raw materials is a special resin used to bind the fiberglass in the moulding phase of production. The production manager, Sizwe, uses an economic order quantity decision$-$making model to determine the size and frequency of resin orders.

Resin is purchased in $50-$liter drums, and $9800$ drums are used each year. Each drum costs R$350.$ The controller estimates that the cost of placing and receiving a typical resin order is R$158.$ The controller's estimate of the annual cost of carrying resin in inventory is $R4\mathrm{.}20$ per drum plus $R1$ insurance cost. Further information that relates to fiberglass surfboards is as follows:

$\backslash$table$[[$Lead time,$10$ to $15$ working days$],[$Average usage,$25$ drums per day$],[$Minimum usage,$10$ drums per day$],[$Maximum usage,$15$ drums per day$]]$

Required

If Sizwe orders $700$ liters of resin in each order placed during the year. Calculate the following:

a$.$ Indicate economic order quantity from above

b$.$ Annual cost of ordering

c$.$ Annual carrying cost