Answer
$1.98 m/s^2$
Work Step by Step
Mass per unit volume is the definition of density. Assuming that the density of Europa is the same as of the Earth's, the radius of Europa can be calculated.
$$\rho_{Europa} = \rho_{Earth}$$
$$\frac{m_{Europa}}{\frac{4}{3}\pi r^3_{Europa}}=\frac{m_{Earth}}{\frac{4}{3}\pi r^3_{Earth}}$$
$$r_{Europa}=r_{Earth}(\frac{m_{Europa}}{m_{Earth}})^{\frac{1}{3}}$$
$$g_{Europa}=\frac{Gm_{Europa}}{r^2_{Europa}}=\frac{Gm_{Europa}}{(r_{Earth}(\frac{m_{Europa}}{m_{Earth}})^{\frac{1}{3}})^2}=\frac{Gm^{1/3}_{Europa}m^{2/3}_{Earth}}{r^2_{Earth}}=\frac{Gm_{Earth}}{r^2_{Earth}}(\frac{m^{1/3}_{Europa}}{m^{1/3}_{Earth}})=g_{Earth}(\frac{m_{Europa}}{m_{Earth}})^{\frac{1}{3}}$$
$$=9.8m/s^2 (\frac{4.9x10^{22}kg}{5.98x10^{24}kg})^{\frac{1}{3}}=1.98m/s^2$$
