Three friends bought 4, 6, and 8 books. the table shows the cost of the books. number of books 4 6 8 cost ($) 30 45 60 what is the constant of proportionality?

Mallory has been offers two different jobs. she can baby sit for 6 hours a week and get $8.50 an hour. or she can work at the library for 14 hours a week and make $5.50 an hour. which job will allow her to save the most money after 6weeks?