A 100-g ball falls from a window that is 12 m above ground level and experiences no significant air resistance as it falls. What is its momentum when it strikes the ground?

Idon’t quite understand this problem

What practical value did astronomy offer to ancient civilizations?

Use the ratio form of kepler’s third law, = , and the data provided to determine the time it takes mars to orbit the sun. round your answer to the nearest tenth. earth’s orbital period = 1.0 earth year earth’s distance from the sun = 1.0 au mars’s distance from the sun = 1.5 au it takes mars about ⇒ 1.8 earth years to orbit the sun.