$3.33 \ imes 10^{-5}\ extrm{ m/s}^2$\r $5.93\ imes 10^{-3}\ extrm{ m/s}^2$ \r The acceleration due to gravity on the Earth's surface due to the sun is 178 times that due to the moon. The tides are cased by the difference in gravitational force between the near and far sides of the Earth. The difference for the moon is $2.2\ imes 10^{-6}\ extrm{ m/s}^2$ whereas for the sun the difference is $1.0\ imes 10^{-6} \ extrm{ m/s}^2$. The difference due to the sun is about half that due to the moon, which is still significant enough to manifest as spring tides every two weeks when the sun-Earth-moon line up.