Part one:

The pendulum in the consists of a $6kg$ disk and two slender rods $AB$ and $DC$ whose

mass per unit length of each is $2k\frac{g}{m}.$ Calculate the position vector of the center of

mass with respect to the reference frame in the figure.

Second part:

The welded slender bar structure in Figure $4$ has a mass per unit length of $2k\frac{g}{m}.$

Calculate the position vector of the center of mass with respect to the reference frame

in the figure.