Two blocks, $M_1$ and $M_2,$ are connected by a massless string that passes over a massless pulley. $M_1$ has a mass of $2\mathrm{.}25$ kg and is on an incline of angle ${}_1=43\mathrm{.}5$ that has a coefficient of kinetic friction ${}_1=0\mathrm{.}205.M_2$ has a mass of $6\mathrm{.}85$ kg and is on an incline of angle ${}_2=34\mathrm{.}5$ that has a coefficient of kinetic friction ${}_2=0\mathrm{.}105.$ The figure illustrates the configuration.

The two$-$block system is in motion, with block $M_2$ sliding down the ramp.

Find the magnitude $a_2$ of the acceleration of block $M_2.$

$a_2=$

$\frac{m}{s^2}$