$\"\"$

Draw the diagram :

$\"\"$

Observe the diagram:

The centroids of the regions are $\"\"$ , $\"\"$ and $\"\"$ .

Mass of the rectangle region is area of the rectangle, $\"\"$ .

The center of mass is $\"\"$ .

$\"\"$

$\"\"$ .

The center of the mass is $\"\"$ .

$\"\"$

The center of mass is $\"\"$ .