The spectrum of light from a star is, to a good approximation, a blackbodyspectrum. The red supergiant star Betelgeuse has Amax = 760 nm. (Notethat this is actually in the infrared portion of the spectrum.) When light fromBetelgeuse reaches the earth, the measured intensity at the earth is 2.9 X10-8 W/m². Betelgeuse is located 490 light years from earth.(a) Find the temperature of Betelgeuse.(b) Find the intensity of light emitted by Betelgeuse. (Hint: Remember thatthis and the measured intensity at the earth are related by an inverse squarelaw.)(c) Find the radius of Betelgeuse. (Assume it is spherical.)

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