Anew pair of shoes costs $50. in this case, money is a _

A medium of exchange.

Explanation:

One of the fundamental functions of money in mainstream economics is being a medium of exchange, in opposition to being a common measure of value, a standard of deferred payment), or a store of value.

Money is a medium of exchange because it´s widely accepted that can be traded for goods and services.

one of the negative side effects were the economic losses the events of september 11th caused. many, many people lost their jobs as a result of a downturn in the economy after the terrorist attacks.

representative government