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The sun can be treated as a blackbody at temperature 5800 K, and solar radiation between...

The sun can be treated as a blackbody at temperature 5800 K, and solar radiation between the wavelengths 0.35 and 0.70 μm is useful for photosynthesis. (a)What is the wavelength λ1 below which 20% of the solar emission is concentrated? (b) What is the wavelength λ2 above which 20% of the solar emission is concentrated? (b) What fraction of total solar radiation is not useful for photo-synthesis?

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