赞题库-背景图
单项选择题



What is the circumference of the circle above
(1)The length of arc XYZ is 18.
(2)r=s

A．条件(1)充分，但条件(2)不充分．
B．条件(2)充分，但条件(1)不充分．
C．条件(1)和(2)单独都不充分，但条件(1)和条件(2)联合起来充分．
D．条件(1)充分，条件(2)也充分．
E．条件(1)和条件(2)单独都不充分，条件(1)和条件(2)联合起来也不充分．
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单项选择题The most widely used therapy for a certain type of ulcer completely heals such ulcers in 44 percent of patients within six months. In a six-month trial of a new therapy for this type of ulcer, 80 percent of ulcers treated achieved significant healing and 61 percent were completely healed. Since the trial treated only ulcers of this type that were worse than average, the new therapy clearly promotes healing more effectively than the most widely used therapy.The answer to which of the following would be most useful in evaluating the argument given

A．What differences are there, if any, in the ways that the two therapies are administered
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E．What percentage of patients involved in the six-month trial of the new therapy were disappointed at the rate of healing that were experiencing

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