The distance of the Sun from Earth is 1.5 × 10¹¹ m, and its angular diameter is (2000) s when observed from the Earth. What is the Sun's actual diameter?
a) 1.5 × 10¹¹ m
b) 7.5 × 10⁷ m
c) 1.5 × 10⁸ m
d) 7.5 × 10⁵ m