The correct option is
B (56a,56a)Let the object is made by three same squares of side
a , the centre of mass of each square will be at the intersection of diagonals of square ,
now coordinates of CM of upper square , (a/2,3a/2) ,
coordinates of CM of lower square at origin , (a/2,a/2) coordinates of CM of lower square (rightmost) , (3a/2,a/2) ,
therefore ,
xcm=m1x1+m2x2+m3x3m1+m2+m3 , ycm=m1y1+m2y2+m3y3m1+m2+m3 ,
mass of all the squares will be same as they have same density and same dimensions (volume) , let mass of each square is m ,
x1=a/2 , x2=a/2 , x3=3a/2 , y1=3a/2 , y1=a/2 , y1=a/2 ,
xcm=ma/2+ma/2+3ma/2m+m+m=5a/6 ,
ycm=3ma/2+ma/2+ma/2m+m+m=5a/6 ,