Given the restrictions on collusion in the US, what techniques do Oligopoly firms use to stay competitive and in business?

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Clooney corp. establishes a petty cash fund for $225 and issues a credit card to its office manager. by the end of the month, employees made one expenditure from the petty cash fund (entertainment, $20) and three expenditures with the credit card (postage, $59; delivery, $84; supplies expense, $49).record all employee expenditures, and record the entry to replenish the petty cash fund. the credit card balance will be paid later. (if no entry is required for a transaction/event, select "no journal entry required" in the first account record expenditures from credit card and the petty cash fund.