The escape velocity of a planet A is $\mathbf { 1 0 ~ k m } / \mathbf { s }$. Another planet B has density equal to $10 \%$ of planet A and radius equal to $10 \%$ of planet A . What is the escape velocity of planet B?
(A) $3.16 \mathrm {~km} / \mathrm { s }$
(B) $1.0 \mathrm {~km} / \mathrm { s }$
(C) $0.316 \mathrm {~km} / \mathrm { s }$
(D) $0.10 \mathrm {~km} / \mathrm { s }$