View full lesson: http://ed.ted.com/lessons/why-do-we-have-to-wear-sunscreen-kevin-p-boyd You already know that a trip to the beach can give you a nasty sunb...
\Andrew Foerster\, \Kevin, P., Boyd\, UVA, UVB, sunscreen, SPF, \importance, of, sunscreen\, \skin, cancer\, wrinkles, ultraviolet, sun, TED, TED-Ed, TEDEduc...