项目跟踪评价中的项目监测作为项目监督和评价的基础，是( )实施项目管理的工具和手段

某住宅小区计划购买并种植甲、乙两种树苗共300株，已知甲种树苗每株60元，乙种树苗每株90元。

（1）若购买树苗共用21000元，问甲、乙两种树苗应各买多少株？

（2）据统计，甲、乙两种树苗每株树苗对空气的净化指数分别为0.2和0.6，问如何购买甲、乙两种树苗才能保证该小区的空气净化指数之和不低于90而且费用最低？

Part 4

Questions 26-45

·Read the following article and choose the best word for each space.
·For questions 26-45, mark one letter A, B, C or D on the Answer Sheet.

iPhone Left in Hot Car for Three Hours

The normally peaceful suburban town of Winnetka is still reeling following the news Monday (26) a local resident, whose name is being (27) by police pending a full investigation, left an iPhone unattended for more than three hours in a car (28) in the hot sun.
"Responding to calls from (29) . passersby, who observed the iPhone sitting in a vehicle in the parking (30) of the Westfield Shopping Center, police arrived on the (31) at approximately 4 p.m. and immediately intervened to save the device," said Winnetka police chief Douglas Blaine. "Security cameras have shown that the iPhone had been in the car— with the doors (32) and the windows rolled (33) —since 1 p.m. Due to the tragic and highly emotional (34) of this case, we cannot say any (35) at this time."
According to official police records, two officers forcibly (36) into the car at 4:07 p.m. and found the iPhone (37) face down on the dashboard. The iPhone at first showed no (38) of life, but after a tense few seconds, officers were able to wake it and get it to (39) to a series of simple touch commands. Police said that if the iPhone were left in the extreme (40) for any longer, it could have died.
The iPhone was rushed by ambulance to a nearby Apple facility for careful (41) .Miraculously, no damage to its memory, screen, or wireless capabilities was reported.
Upper-middle-class suburbanites from all over the North Shore area have reacted to the near-tragedy with an unprecedented outpouring of (42) . Hundreds of cards and letters have come streaming in, and local talk radio shows have been flooded (43) calls demanding that the iPhone’s (44) be prosecuted. Many have come forward offering to take the iPhone into their custody, and still (45) have donated free downloads, ringtones, and MP3s to the victimized object.

A．this

B．that

C．which

D．what

某县审计局4月20日开会决定对该县国有企业A进行审计，22日该审计局的一名审计人员先期到达A企业进行审计，审计过程中发现A企业与该县另一企业B之间的一笔购销木材合同存在疑点，遂决定到B企业进行调查。4月29日，该审计局的两名审计人员来到B企业，并向B企业的负责人口头说明了自己的身份，要求其提供与A企业木材购销合同的相关情况。该审计局的上述审计活动中，哪些不符合关于审计程序的法律规定？

A．实施审计前未组成审计组

B．实施审计前未向被审计单位的上级主管部门通报情况

C．实施审计3日前未向被审计单位送达审计通知书

D．审计人员进行调查时，未出示审计人员的工作证件和审计通知书副本

抗微生物药物联合应用的指征是()

A.病因未明的严重感染

B.单一抗微生物药不能控制的严重混合感染

C.单一抗微生物药不能控制的严重感染

D.需要长期用药而细菌容易产生耐药性者

E.为了减轻毒性较大的抗微生物药物的剂量，减轻其毒副作用

旅游的本质特征是流动，旅游消费受许多因素的影响与制约，呈现出（）的特点。

A.无形性

B.易波动性

C.享受性

D.选择性