Masses $1,2$ and $3$ are released from rest. Mass $1M_1=50kg$ slides across a surface with a coefficient of kinetic friction $=0\mathrm{.}3.$ The mass of the wheel is $M_3=60kg$ and its radius is $r=0\mathrm{.}2m.$ Mass $2$ has a mass $M_2=100$ kg $.$ What is the acceleration of Mass $2?$ The rotational inertia of the wheel is $I=\frac{1}{2}m{r}^2$