11But I got only A).
U see as avinav has done, \omega=5rad/sec, from which \boxed{T=\frac{2\pi}{5}}.
Now since initial energy should be the same as the final energy, so we get \frac{1}{2}kx^2=\frac{1}{2}m\omega^2A^2\Rightarrow \boxed{A=20cm}....
Thus b) get's flawed.
|a_{max}|=\omega^2A=5m/s^{-2}, d) gets deleted....similarly |v_{max}|=\omega A=1m/s^{-1}.....c) is wrong.
