Betelgeuse is a 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 5.67 × 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
E
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