级数的和为（）。
A．A
B．B
C．C
D．D
参考答案：D
解析：
[点评] 本题方法是利用幂级数求和函数方法求数项级数的和。
稳定极限描述错误的是（）
A.正常人自然平稳站立时前后摆动的角度是12.5°
B.左右方向最大倾斜角度是16°
C.左右方向摆动围成一个椭圆形
D.稳定极限支持面积的大小取决于支持面的大小
E.重心超出稳定极限时平衡即被破坏不能调节
The nurse is caring for a client with bipolar disorder in a manic state. Which of the following nursing interventions should be included in the plan of care（）
A. Allowing the client to exhibit hyperactive, demanding, manipulative behavior without setting limits.
B. Listening attentively with a neutral attitude and avoiding power struggles.
C. Offering high-calorie meals and ply encouraging the client to finish all food.
D. Insisting that the client remain active through the day so that he’ll sleep at night.
的和为（）。
的和为（）。