Multiple Choice
Betelgeuse is a red supergiant star in the constellation Orion. It radiates heat at the rate of 2.70 × 1030 W and has a surface temperature of 3000 K. Assuming that it is a perfect emitter, what is the radius of Betelgeuse? The Stefan-Boltzmann constant is 5.670 × 10-8 W/m2 · K4.
A) 7.80 × 1010 m
B) 8.70 × 1010 m
C) 1.40 × 1011 m
D) 1.90 × 1011 m
E) 2.16 × 1011 m
Correct Answer:

Verified
Correct Answer:
Verified
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