Company A offers a starting salary of $28000 with a raise of $3000 each year, Company B offers a starting salary of $36000 with a raise of $2000 per year. Company C offers a starting salary of $18000. After how many years would the salaries for Company A and Company B be the same? How much raise per year would Company C have to offer to equal the salaries of Company A and Company B in the year in which the salaries of those two companies are the same?