A uniform rectangular plate made from steel is shown in the diagram below.

The plate which is $5$ mm thick has a semi$-$circular section cut out and filled with a uniform material made from lead while a triangular section has also been cut out and filled with a uniform material made from aluminium.

The density of steel is $8000k\frac{g}{m^3},$ lead is $11300k\frac{g}{m^3}$ and aluminium is $2700k\frac{g}{m^3}.$

Determine the horisontal and vertical coordinates of the centre of gravity of the plate with reference to point O$.($Answers to the nearest whole number and in millimeters$).$

$($All dimensions are in mm $).$