Answer each of the following questions and don't forget to indicate the sign $($positive or negative$).$

A seller earns $$50,000$ in total revenue. Their implicit costs of production are $$18,000$ and their explicit costs of production are $$30,000.$ How much accounting profit did they earn?

Maxim is the owner of a clothing store. Last year, their total revenue was $$180,000,$ their rent was $$5,000,$ their labor costs were $$21,000,$ and their overhead expenses were $$4,000.$ Maxim could earn $$66,000$ per year working at another nearby clothing store. From this information, we know that their accounting profit was:

Suppose that a firm produces $400$ units a year and sells them all for $$500$ each. The explicit costs of production are $$141,000$ and the implicit costs of production are $$16,000.$ How much is the firm's accounting profit?