How to #11

The mysterious visitor that appears in the enchanting story The Little Prince was said to come from a planet that "was scarcely any larger than a house!" Assume that the mass per unit volume of the planet is about that of Earth and that the planet does not appreciably spin. Take the diameter of the planet to be 18 m. Approximate (a) the free-fall acceleration on the planet's surface and (b) the escape speed from the planet. (a) Number i Units (b) Number i Units