Calculus question please explain with steps

A company knows that the unit cost C and the unit revenue R from the production and sale of x units are related by c=- R2 + 11,210. Find the rate of change of unit revenue when the unit cost is changing by sul/unit and the unit revenue is $2000. O A) $324.50/unit OB) $724.25/unit O c) $110.00/unit OD) $1124.00/unit Question 2 (1 point) Solve the problem. Assume that the profit generated by a product is given by p()-4x where x is the number of units sold. If the profit keeps changing at a rate of $70 per month, then how fast are the sales changing when the number of units sold is 1500? (Round your answer to the nearest dollar per month.) A) $6778/month O B) $216,887/month O C) $13,555/month OD) $9/month