Which is true about UVA and UVB rays?
A. Both rays can be blocked 100% by sunscreen
B. UVA pr...
Which is true about UVA and UVB rays?
A. Both rays can be blocked 100% by sunscreen
B. UVA protects the surface, UVB protects beneath the surface
C. UVB rays cause burning, UVA rays cause premature aging
D. UVA rays cause burning, UVB rays cause premature aging
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Answers: 2
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