【单选题】北美奇瓦瓦沙漠中的啮齿动物和蚂蚁均以植物种子为食,啮齿动物喜食大粒的植物种子,蚂蚁喜食小粒的植物种子。 1974—1977 年间连续研究两种动物的关系,结果如图所示。下列分析研究结果,不合理的是
【单选题】We want to rent a bus which can ______ 40 people for our trip to Beijing.
【单选题】听力原文:W: I want to know if it is possible to see the apartment before we rent it? M: You bet, it's vacant. Q: What does the man mean? (14)
A.
No one lives there now.
B.
You can see it after your vacation.
C.
You'd better make an appointment.
D.
It's a beautiful place.
【单选题】如果对系统的客观规律一无所知,只能从系统的测试数据获取系统模型,则该问题为
【判断题】发动机维护作业内容包括清洁、检查、补给、润滑、紧固、调整