the magnitude of the weight of a 21.0 kg dog on the surface of saturn would be ____N [towards Saturn's center].

Answer 1

Hard to say because what is the ground on a gas planet but where the gas pressure is about the same as air pressure here the g is about 10.58 m/s^2 as opposed to 9.81 m/s^2 here
therefore m g = 21.0 * 10.58 = 222 Newtons