Planet Z-34 Has a Mass Equal to One-Third That of Earth

Multiple Choice

Planet Z-34 has a mass equal to one-third that of Earth and a radius equal to one-third that of Earth.With g representing,as usual,the free-fall acceleration at the surface of Earth,the free-fall acceleration at the surface of Z-34 is

A) g/3.
B) 3g.
C) 6g.
D) g/9.
E) 9g.