A Giant Star Radiates Energy at the Rate of 3

Multiple Choice

A giant star radiates energy at the rate of 3.0 × 10³⁰ W,and its surface temperature has been measured to be 3000 K.Assuming that it is a perfect emitter,what is the radius of this star? (σ = 5.67 × 10^-8 W/m² ∙ K⁴)

A) 7.8 × 10¹⁰ m
B) 8.7 × 10¹⁰ m
C) 1.4 × 10¹⁰ m
D) 1.9 × 10¹¹ m
E) 2.3 × 10¹¹ m