没问过的taotao gwd 17-23，gwd总结里是17-11

Because visual inspection cannot reliably distinguish certain skin discolorations from skin cancers, dermatologists at clinics have needed to perform tests of skin tissue taken from patients.  At Westville
                Hospital, dermatological diagnostic costs were reduced by the purchase of a new imaging machine that diagnoses skin cancer in such cases as reliably as the tissue tests do.  Consequently, even though the machine is expensive, a dermatological clinic in Westville is considering buying one to reduce diagnostic costs.

Which of the following would it be most useful for the clinic to establish in order to make its decision?

1. Whether the visits of patients who require diagnosis of skin discolorations tend to be shorter in duration at the clinic than at the hospital

2. Whether the principles on which the machine operates have been known to science for a long time

3. Whether the machine at the clinic would get significantly less heavy use than the machine at the hospital does

4. Whether in certain cases of skin discoloration, visual inspection is sufficient to make a diagnosis of skin cancer

5. Whether hospitals in other parts of the country have purchased such imaging machines

我选的是e，答案是c

c想的通，e为什么又不对呢

文章都是说在Westville 的医院和诊所啊

没有提到其它地方啊

Westville 这个地方医院买一台，Westville 这个地方的诊所也想买一台

问评价，诊所要考虑点什么

当然要考虑使用的情况啊，要是一年没几个病人，买个好机器有什么用，成本如何收回？放在那里生锈？

E说其它地方的医院是不是买了，有什么意义呢？难道医院买，诊所就一定要买吗？

谢谢 斑竹

diagnostic costs were reduced by the purchase of a new imaging machine that diagnoses skin cancer in such cases as reliably as the tissue tests do. 

机器主要是用来诊断skin caner的，所以有关的是做skin cancer诊断的病人数量，

A答案是关于诊断skin discolorations 的来访人数，是无关选项

D. 只说 certain cases ，所以绝对错

只能选C （因为直接针对关键点：cost）

但C这个答案让人很不喜欢

原文说 反正要买个仪器能检验个啥，然后 D这个地方的医院买了大幅度降低了检验啥的cost,尽管贵 D那个地方的诊所也打算去买。

问评估。答案要说到的是医院和诊所或者成本就算相关

A 说duration在医院和政所比较。（沾点）

B 说原理是不是被科学家知道。（无关之家排除）

C 说在诊所 用的是不是比医院少。（也沾点）

D 说v这个检查是不是必要（无关）

E 说在Ｄ其他地方的医院是不是也买了。（这个也无关啊）

A 和 C比 明显C好。 因为A 还要想 duration和使用频率的关系。C 明显比A 更不要想，直接告诉你用的少。为什么不选呢？