华夏族是汉族的前身，华夏族的主体是 ①炎帝部族②蚩尤部族③黄帝部族④尧部族[ ]

计算：sin²45°+cos²45°=______．

编制统计表有哪些注意事项？

下列保险中，属于商业保险的有( )。

A．保证保险

B．劳动工伤保险

C．信用保险

D．健康保险

E．责任保险

What can be inferred about old nepotism

A．Parents maximized the family advantages for the benefits of their children.

B．Parents gave full respect to the likes and dislikes of their children.

C．Children had their own choice of career and marriage.

D．Children willingly lived on the expectations of their families.

矿山救护指战员，必须经过救护理论及技术、技能的培训，并经考核取得合格证后，才能从事（）。