A spacecraft is observed at its periapsis on March 21st (Vernal Equinox.) The range measurement indicates that the spacecraft is at 20,0000 km...

A spacecraft is observed at its periapsis on March 21st (Vernal Equinox.) The range measurement indicates that the spacecraft is at 20,0000 km distance from the center of Earth. The velocity measurement provides the velocity vector in the ECI frame as v(vector)_p = -3i + 4j, where i and j are the unit vectors of the ECI frame. The spacecraft orbit has zero inclination.Find the periapsis position vector (r(vector)_p) in the ECI frame.