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发帖数: 457 | 1 Q: What are key factors to consider when selecting sunscreen?
A: A thorough explanation involves many details, but here's the short answer
includes ingredients that are effective against both UVA and UVB light (
sometimes called a "broad-spectrum" sunscreen).
offers a sun protection factor (SPF) of at least 15 but, for extended
outdoor recreation, preferably 30.
Q: Why should we be concerned about sunlight?
A: Sunlight includes both visible light and shorter waves of invisible
ultraviolet (UV) r |
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