From a rectangular metal sheet of side 30 cm and 40 cm, a circular sheet as big as possible, is cut off. Find the Area of the remaining sheet.

• A. \[492.86\,\,c{{m}^{2}}\]     
• B. \[429.68\,\,c{{m}^{2}}\]
• C. \[892.86\,\,c{{m}^{2}}\]                 
• D. \[426.45\,\,c{{m}^{2}}\]