K$-$Too Everwear Corporation can manufacture mountain climbing shoes for $$19\mathrm{.}55$ per pair in variable raw material costs and $$18\mathrm{.}06$ per pair in variable labor expense. The shoes sell for $$95$ per pair. Last year, production was $140,000$ pairs. Fixed costs were $$780,000.$

a$.$ What were total production costs?

b$.$ What is the marginal cost per pair?

c$.$ What is the average cost?

d$.$ If the company is considering a one$-$time order for an extra $12,000$ pairs, what is the minimum acceptable total revenue from the order?