英语翻译after selecting tentative values of length,bredth ,depth

英语翻译
after selecting tentative values of length,bredth ,depth and displacement,the designer must achieve a weight balance,he must also select a moment balance,beacause the center of grative in both logitudinal and virtical directions must provide satisfactory trim and stability
After selecting tentative values of length,breadth,depth,draft,and displacement,the designer must achieve a weight balance.He must also select a moment balance because centres of gravity in both longitudinal and vertical directions must provide satisfactory trim and stability.Additionally,he must estimate the shaft horsepower required for the specified speed; this determines the weight of machinery.The strength of the hull must be adequate for the service intended,detailed scantlings (frame dimensions and plate thicknesses ) can be obtained from the rules of the classification society.These scantings determine the requisite weight of hull steel.
完整是这样的