What are the steps on solving this problem?

21.6 A spring of spring constant k = 50N/m is mounted on a horizontal surface with uncompressed position x = 0. The surface is frictionless for x 0. A mass m = 3kg is placed against the spring and pulled back to position x =-0.7m. The mass is then released and leaves the spring at x = 0. At what position x = D does the mass come to rest? (A) 1.9 m (B) 2.8 m (C) 1.2 m (D) 2.1 m (E) 3.6 m - No friction ( HA )