跟单员花费精力最多的跟单环节是（）
A. 制作采购单
B. 内部报批
C. 采购跟单跟踪
D. 原材料检验
The confidence interval for the sample regression function slope
A. can be used to conduct a test about a hypothesized population regression function slope.
B. can be used to compare the value of the slope relative to that of the intercept.
C. adds and subtracts 1.96 from the slope.
D. allows you to make statements about the economic importance of your estimate.
오늘 수업에 학생들이 많이 _____________.
A. 없어요
B. 안 나와요
C. 빠졌어요
D. 삐졌어요
영수 씨는 어제 축구를 ____________ 발목을 다쳤어요.
A. 했다가
B. 했으면
C. 하면
D. 하다가
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