Solve the Problem $R=36 x-0.7 x^{2}$ And $C=6 x+13$ , Where $x$ Is the Daily Production, Find the Rate of Change of x-0.7

Solve the problem.
-Given the revenue and cost functions $R=36 x-0.7 x^{2}$ and $C=6 x+13$ , where $x$ is the daily production, find the rate of change of profit with respect to time when 15 units are produced and the rate of change of production is 4 units per day.

A) $\$ 114.40$ per day
B) $\$ 99.00$ per day
C) $\$ 36.00$ per day
D) $\$ 60.00$ per day