The displacement time graph of a particle executing SHM is given in figure: (sketch is schematic and not to scale)

Which of the following statements is/are true for this motion?
(A) The force is zero at $$t = \frac{3T}{4}$$
(B) The magnitude of acceleration is maximum at $$t = T$$
(C) The speed is maximum at $$t = \frac{T}{4}$$
(D) The P.E. is equal to K.E. of the oscillation at $$t = \frac{T}{2}$$

Displacement from the graph: $$x\left(\frac{T}{4}\right) = 0,\ x\left(\frac{T}{2}\right) = -A,\ x\left(\frac{3T}{4}\right) = 0,\ x(T) = A$$

Checking statement (A): $$F = -kx \implies F\left(\frac{3T}{4}\right) = -k(0) = 0$$

Checking statement (B): $$|a| = \omega^2|x| \implies |a(T)| = \omega^2 A = |a|_{\text{max}}$$

Checking statement (C): $$v = \omega\sqrt{A^2 - x^2} \implies v\left(\frac{T}{4}\right) = \omega\sqrt{A^2 - 0^2} = \omega A = v_{\text{max}}$$

Checking statement (D): $$U = \frac{1}{2}kx^2 \implies U\left(\frac{T}{2}\right) = \frac{1}{2}kA^2 = E_{\text{total}} \implies K = 0$$