A spacecraft travels along a straight line from Earth to the Moon. At what distance from Earth does the force of gravity exerted by Earth on the coasting spacecraft cancel the force of gravity exerted by the Moon on the spacecraft? Use the Moon's orbit semimajor axis as a distance between planets.

Two students, each riding bicycles, start from the same apartment building and ride to the same building on campus, but each takes a different route. the first student rides 1100 m due east and then turns due north and travels another 1430 m before arriving at the destination. the second student heads due north for 1930 m and then turns and heads directly toward the destination. at the turning point, how far is the second student from the destination?