As we know that angular frequency of SHM is given as
[tex]\omega = 2\pi f[/tex]
f = 4.91 Hz
[tex]\omega = 2\pi (4.91)[/tex]
[tex]\omega = 30.85 rad/s[/tex]
now we know that maximum acceleration during SHM is given by
[tex]a_{max} = \omega^2 A[/tex]
[tex]a_{max} = 30.85^2 A[/tex]
[tex]135 m/s^2 = 951.75(A)[/tex]
now we will have
[tex]A = 0.142 m[/tex]
so its maximum displacement will be 14.2 cm