Can someone give me a step-by-step explanation on this?

The revenue from producing electric bicycles can be modeled by the function R(q) = q2(197.2 - 2.8q) and their cost can be modeled by the function C(g) = 589.1 + 57.9q where q is the number of thousands of electric bicycles sold/produced and costs and revenues are in thousands of dollars. How many thousands of electric bicycles should the manufacturer need to break even