2. A simple spring-mass system consists of a block of mass m attached to a spring with spring constant k. What is the speed of the block as it passes through the equilibrium position x0, given that the initial displacement is A? (A) A(kx₀²/m)¹/² (B) A(k/m)¹/² (C) 1/2(kx₀²) (D) (2gA)¹/² (E) kx₀