雷达对抗的基本内容可分为（）、（）和（）。
参考答案：雷达侦察；雷达干扰；反辐射攻击
胰岛素瘤是来源于__________的一种罕见肿瘤。
The least accurate statement about measures of dispersion for a distribution is that the:（）
A. range provides no information about the shape of the data distribution.
B. mean absolute deviation will always be smaller than the standard deviation.
C. arithmetic average of the deviations around the mean will always be equal to one.
