Cash is king, but it's also insured deposits (like CDs and demand deposits), and money market instruments (like commercial paper and Treasury bills). So what makes not-cash, cash? Anything in your account that is either straight-up cash (it's got a picture of some old dude on it), or that can be liquidated quickly, is considered cash.
Things like T-bills, commercial paper, banker's acceptance notes, and repurchase agreements are considered cash equivalents if they mature in three months or...
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