What are the physical quantitise having maximum value at the mean position in SHM?

The value of phase at maximum distance from the mean position of a particle in S.H.M. is :

calculate velocity of a particle executing S.H.M and show that it is maximum at the mean position and minimum (i.e. zero) at the extreme position.

The frequency of oscillation of a particle executing SHM with amplitude A and having velocity 'v' at the mean position is

A graph between velocity and displacement of a particle performing SHM is shown. Find the acceleration when the particle is at half of maximum displacement from mean position.