If, in monopoly market, the demand for a product is p=2100 - x and the revenue is r=px, where x is the number of units sold what price will the maximize revenue?

In the field of thermodynamics, rankine is the unit used to measure temperature. one can convert temperature from celsius into rankine using the formula , what is the temperature in celsius corresponding to r degrees rankine? a. 9/5(c - 273) b. 9/5(c + 273) c. 5/9( c - 273) d. 5/9( c + 273)