A man stands on a platform that is rotating without friction with an angular speed of $1\mathrm{.}25$ rev$/$s; his arms are outstretched and he holds a brick in each hand. The rotational inertia of the system consisting of the man, bricks $,$ and platform about the central axis is $6\mathrm{.}52$ kg$*$m$^2,($a$)$ What is the resulting angular speed of the platform and $($b$)$ what is the ratio of the new kinetic energy of the system to the original kinetic energy?