Two spheres are each rotating at an angular speed of $22\mathrm{.}0ra\frac{d}{s}$ about axes that pass through their centers. Each has a radius of $0\mathrm{.}520$ m and a mass of $1\mathrm{.}57$ kg $.$ However, as the figure shows, one is solid and the other is a thin$-$walled spherical shell. Suddenly, a net external torque due to friction $($magnitude $=0\mathrm{.}340N*m)$ begins to act on each sphere and slows the motion down. How long does it take $($a$)$ the solid sphere and $($b$)$ the thin$-$walled sphere to come to a halt?

$($a$)$ Number

Units $$

$($b$)$ Number

i

Units