A body of mass m =

(kg) is attached to the end of a spring with Hooke's constant k = 50 (N/m) and is set in motion with initial position x(0) =

(m) and initial velocity x'(0) = -10 (m/s). (The mass is displaced to the right and moving to the left at time t = 0).
Find (a) the position x(t) of the body at later times t, (b) amplitude, (c) frequency, and (d) period of its oscillation.