what's the frequency?

11. A box of a certain mass is attached to a spring of spring constant 7.0 N/m and experience simple harmonic motion with an amplitude of 0.2 m. When the position of a box is at 0.4 A its speed is measured to be + 0.25 m/s. (Hint: x(t) = Asinwt). Calculate the angular frequency (w). (4) A) 4.22 Hz B) 3.46 Hz C) 2.72 Hz D) 1.36 Hz E) 0.46 Hz