A planet of radius `R_(p)` is revolving around a star of radius `R^(**)`, which is at temperature `T^(**)`. The distance between the star and the planet is d. If the planet's temperature is f `T^(**)`, then f is proportional to

Options

A. `sqrt(R^(**)//d)`
B. `R^(**)//d`
C. `R^(**)R_(P)//d^(2)`
D. `(R^(**)//d)^(4)`

Answer

A