At the high level of activity in November, $7,000$ machine hours were run and power costs were $$12,000.$ In April, a month of low activity, $2,000$ machine hours were run and power costs amounted to $$6,000.$ Using the high$-$low method, the estimated fixed cost element of power costs is

a$.$ $$12,000.$

b$.$ $$6,000.$

c$.$ $$3,600.$

d$.$ $$8,400.$

Schmidt Corporation produces a part that is used in the manufacture of one of its products. The costs associated with the production of $10,000$ units of this part are as follows:

$\backslash$table$[[$Direct materials,$$45,000$