桌类家具高度尺寸:700mm、720mm、740mm、760mm四个规格···································································椅凳类家具的座面高度:400mm、420mm、440mm三个规格································································桌椅高度差应控制在280至320mm范围内··················································································正确的桌椅高度应该能使人在坐时保持两个基本垂直:一是当两脚平放在地面时,大腿与小腿能够基本垂直·······································································································································