Timothy, a cashier, is given a twenty-dollar bill at his store. he is suspicious of the customer and wants to make sure the currency is real. which would be a clue that the currency is counterfeit?

there are watermarks in the paper bill.

there is a security thread in the paper bill.

there is no gold standard backing the bill.

there is no change in the color of the bill's ink.

Firms like papa john’s, domino’s, and pizza hut sell pizza and other products that are differentiated in nature. while numerous pizza chains exist in most locations, the differentiated nature of these firms’ products permits them to charge prices above marginal cost. given these observations, is the pizza industry most likely a monopoly, perfectly competitive, monopolistically competitive, or an oligopoly industry?