Finding the phase constant for simple harmonic motion

[Bugsy23]

Homework Statement

I need to find the speed, at time t=0.015s, of a hydraulic valve component undergoing sinusoidal vibrations. The frequency of the vibrations is 25Hz, the amplitude is 2cm and the angular frequency is 157 s^-1

Homework Equations

The equation for speed of sinusoidal vibrations I have is
v_x(t)=Aw sin(wt+$$\phi$$+pi/2)

The Attempt at a Solution

So far the values I have are
v_x(t)=(0.02*157)*sin(157*0.015)+?+pi/2)
But I can't find anywhere how you're supposed to calculate the phase constant

 

[vela]

There's not enough information to solve the problem. Did you state the problem exactly as it was worded?