$90 - statistics for engineering and the sciences, brand new and unused, 5th edition hardcover

$30 - vector calculus by colley, used and scuffed cover but no highlighting or marks inside, 2nd edition hardcover

$50 - data analysis and graphics using r (maindonald and braun), brand new and unused hardcover

$60 - intermediate microeconomics by varian, brand new and still in shrink wrap, 7th edition softcover (international edition