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Henry Gu is a retired math teacher in New York City. He is an adjunct professor at Fordham University. He has taught all level Math, Physics, and Engineering courses for more than 15 years. He has published a number of Math Regents review books and an AP Calculus review book.
When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.