A seller is considering extending trade credit to an existing customer who has been buying on cash terms. The customer has just placed a sales order $($cash terms$)$ for immediate delivery of $50$ units at a sales price per unit of $$1,300.$ The customer states that they will increase their sales order by $20\%$ if they receive a $90-$day credit period. Variable costs are $$845$ per unit and involve an immediate cash outflow. If the seller has an annual opportunity cost rate of $4\mathrm{.}3\%,$ what is the NPV of extending credit to the customer?

a$)$ $$2,270$

b$)-$$$3,732$

c$)-$$$2,270$

d$)$ $$3,732$