1. =The problem statement, all variables and given/known data Kepler's law of planetary motion says that the square of the period of a planet (T^2) is proportional to the cube of the distance of the planet from the Sun (r^3). mars is about twice as far from the Sun as Venus. How does the period of Mars compare with the period of Venus? 2. Relevant equations 3. The attempt at a solution Does this mean that the period of Mars is about twice as long as Venus'? T^2=Kr^3 2T^2=K2r^3 ???