A meter-stick is pivoted at its 50 cm mark however doesn’t balance because of the non-uniformities in its material which cause its center of gravity to be displaced from the geometrical center. Though, if weights of 150 g and 200 g are positioned at the 10 cm and 75 cm marks, correspondingly, balance is obtained. The weights are then interchanged and balance is again achieved by shifting the pivot point to the 43 cm mark. Determine the mass of the meter stick and the position of its center of gravity.