题干
24. —Mr Smith, ______ John ______ this week? A friend of his is coming to see him this afternoon.
—No. He is on holiday.
A：has; worked
B：is; working
C：did; work
D：does; work
答案(点此获取答案解析）
B
，标准差
，总体服从正态分布，若云龙一中录取率为40%，那么云龙一中录取分数线可能划在（已知
(0.25)＝0.6） ( )