【简答题】What did the thief take from the shop?
【单选题】— What did you do this morning? — I went _____. [ ]
【简答题】元组解包的概念?举例说明?(每问 3 分,共 6 分)
【简答题】厚度为 2.0m 的烟气层, 测得 有 30% 的光穿过,计算单位厚度上烟气的光学密度为( )及烟气的消光系数为( ) m -1 。结果保留三位有效数字,不用写单位。
【单选题】What is special about the shop's service?
A.
The shop guarantees the battery for a year.
B.
The man will clean it at no extra charge.
C.
The man can repair watches very quickly.
D.
The shop is offering a special discount.
【单选题】—What’s Jack up to in the shoe shop? He’s there for ages. —It’s ______ that he hasn’t decided which pair to buy.
【简答题】有一组样本数据8,x,10,11,9,已知它们的平均数为10,则这组数据的方差s 2 = ▲ .