SF3102型电动轮汽车转向系统采用（）。
A.常流式全时间动力转向
B.常压式全时间动力转向
C.两者都有
D.都不对
参考答案：A
润滑油油位降低可能的原因？
An analysis determined that approximately 99 percent of the observations of daily sales for a company were within the interval from $ 250000 to $ 580000 and that daily sales for the company were normally distributed. The mean daily sales and standard deviation of daily sales, respectively, for the company were closest to: Mean daily sales Standard deviation of daily sales（）
A. $ 415000 $ 41667
B. $ 415000 $ 55000
C. $ 355115 $ 41667
