Elm uses the high-low method of estimating costs. Elm had total costs of $250,000 at its lowest level of activity, when 5.000 units were sold. When at lyhest levele O $45.50 $28.00 $52.71 $70.00 ity, when 5,000 units were sold. When, at its highest level of activity, sales equaled 10,000 units, total costs were $390,000. Em would extent are operate