A manufacturer models the production of x units (x>0) with the following functions:
Variable cost per batch: v(x)=5x+20,
Fixed cost: c(x)=1000 (in rupees),
Selling price per unit: r(x)=50−x−21.
a. (i) Write the total revenue function R(x) and the total cost function C(x).
b. (ii) Derive the average profit per unit A(x)=xR(x)−C(x) and simplify it.
c. (iii) Determine the domain of A(x) and interpret the practical meaning of any restrictions obtained.