设在10件产品中有4件一等品,6件二等品,现从中随机取出2件,已知其中至少有1件是一等品,则2件都是一等品的概率为().
A. 2/15
B. 1/15
C. 1/5
D. 2/5
E. 3/5
查看答案
What must the woman do to know the way of making money?
A. Send a postal for five pence and an envelope with a stamp and her address.
B. Continue to read the latter half of the advertisement.
C. Send some money.
D. Buy some envelopes.
Which of the following is NOT true?
A. The prices of many things have gone up in the last month.
B. The woman pays twenty dollars for the ticket.
C. The prices of the ticket have changed by two dollars.
肾细胞属于()。
A. 增值细胞
B. 静息细胞
C. 终端分化细胞
D. 周期细胞
E. 成体干细胞
This passage is______.
A. a humor.
B. a short story.
C. an advertisement.
D. a serious article.