In spring mass system we know that angular frequency is given as
[tex]\omega = 2\pi f[/tex]
f = 8.38 Hz
[tex]\omega = 2\pi(8.38)[/tex]
[tex]\omega = 52.65 rad/s[/tex]
now we know that speed of SHM at its extreme position is given by
[tex]v = A\omega[/tex]
here we know that
A = 17.5 cm
[tex]v = 0.175 (52.65)[/tex]
[tex]v = 9.21 m/s[/tex]
so maximum speed is 9.21 m/s