Assume that a company had sales per share of $$18\mathrm{.}90$ at the end of $2023.$ Sales are expected to grow by $6\%$ per year for the next five years. After that, the company is expected to grow $4\%$ into perpetuity. The company has a profit margin of $10\%$ and a return on equity of $8\%.$ The cost of equity is estimated at $8\%.$

a$)$ Use the Free Cash Flow to Equity $($FCFE$)$ model to value the company$$s stock.

b$)$ If there is a $-1\%$ change in the cost of equity, without any calculations, what will happen to the stock$$s value? Explain your answer.

c$)$ Assume the company$$s owner asks you to use the Free Cash Flow to the Firm $($FCFF$)$ model to value the company$$s stock instead of using the FCFE model, and you can access to the company$$s financial statement reports. Explain why or why not you should use FCFF model to help the owner.