Ｍａｔｈ一直不好。。ＪＪ和prep一起联系。。。
3.
How many different prime numbers are factors of the positive integer n ?
(1) Four different prime numbers are factors of 2n.
(2) Four different prime numbers are factors of n2.
答案选Ｂ，我选Ｄ
根据１，Ｎ应该除２以外有３个prime factors 不知哪里想错了
23.
At least 100 students at a certain high school study Japanese. If 4 percent of the students at the school who study French also study Japanese, do more students at the school study French than Japanese?
(1) 16 students at the school study both French and Japanese.
(2) 10 percent of the students at the school who study Japanese also study French.
答案B 我选D
16/ 4%=400>100
40.
Beth's bank charges a service fee on a regular checking account for each month in which the balance on the account falls below $100 at any time during the month. Did the bank charge a service fee on Beth's regular checking account last month?
(1) During last month, a total of $1,000 was withdrawn from Beth's regular checking account (2) At the beginning of last month, Beth's regular checking account balance was $500.
答案E，我选C； 这题完全不明白为什么会是E，难道题目同时考虑存钱的因素？ | 
