营养素密度
参考答案：
即食物中某营养素满足人体需要的程度与其能量满足人体需要程度之比值。营养素密度=（一定量食物中某营养素含量/该营养素的推荐摄入量）
I hold it in my hands as if holding all the lives in the world, ______what to do with it. [ ]
A. didn't know
B. not knowing
C. not having known
D. not know
模板中的（）是指可以创建包含重复行的表格格式的可编辑区域。
