There are hundreds of high school students in need of algebra tutoring services in philadelphia. dozens of companies offer tutoring services, and the parents who seek out tutors view the quality of the tutoring at the different companies to be largely the same. the government has granted the u. s. postal service the exclusive right to deliver mail. a few major airlines account for the vast majority of air travel. consumers view all airlines as providing basically the same service and will shop around for the lowest price. there are hundreds of colleges that serve millions of students each year. the colleges vary by location, size, and educational quality, which enables students with diverse preferences to find schools that match their needs.