Solve the Problem $C$ And the Unit Revenue $R$ From the Production and Sale Of

Multiple Choice

Solve the problem.
-A company knows that the unit cost $C$ and the unit revenue $R$ from the production and sale of $x$ units are related by $\mathrm { C } = \frac { \mathrm { R } ^ { 2 } } { 122,000 } + 11,397$ . Find the rate of change of unit revenue when the unit cost is changing by $\$ 11 /$ unit and the unit revenue is $\$ 1000$ .

A) $\$ 671.00 /$ unit
B) $\$ 55.00 / u n i t$
C) $\$ 905.35 /$ unit
D) $\$ 1139.70 /$ unit