$3$: PLEASE SOLVE USING EXCEL A manufacturer can sell product $1$ at a profit of $$2$ per unit and product $2$ at a profit of $$5$ per unit. Three units of raw material are needed to manufacture $1$ unit of product $1,$ and $6$ units of raw material are needed to manufacture $1$ unit of product $2.$ A total of $120$ units of raw material are available. If any product $1$ is produced a setup cost of $$10$ is incurred; if any product $2$ is produced a setup cost of $$20$ is incurred. a$.$ Formulate this problem. b$.$ Solve this problem using Excel.