阳黄与阴黄的主要鉴别要点是（） A.小便黄与不黄 B.病程较长与较短 C.黄疸鲜明与

The next two questions refer to the following passage:

A pharmaceutical company tested a new painkiller on 1,000 lab rats that were fed large doses of the painkiller for a two-month period. By the end of the experiment, 39 of tile rats had died. The company concluded that the painkiller was sufficiently safe to test on humans.

Which of the following, if true, would cast the most doubt on the pharmaceutical company’s conclusion ？（）

A. Fifteen of the 39 dead rats were later found to have died of a rare form of liver cancer that is generally seen in only 1 out of 600,000 lab rats.

B. The director of the experiment, although a respected scientist, is not a medical doctor, and therefore will not be able to continue as director of the experiment once it switches from animal to human trials.

C. Although the painkiller in question has been shown to block certain forms of pain, its duration of efficacy is less than that of other painkillers currently on the market.

D. Human trials of another drug produced by this pharmaceutical company were called off after 30 out of 1,000 rats died of heart failure during the animal testing phase of the experiment.

E. The pharmaceutical company is eager to introduce new drugs to the market because its best-selling product, a drug that reduces blood pressure, will soon lose its patent protection.

（6分）氢氧化钡是一种使用广泛的化学试剂。某课外小组通过下列实验测定某试样中Ba(OH)₂·nH₂O的含量。

（1）称取3.50g试样溶于蒸馏水配成100mL溶液，从中取出10.0mL溶液于锥形瓶中，用0.100mol/LHCl溶液中和，共消耗盐酸20.0mL（杂质不与酸反应），求试样中氢氧化钡的物质的量。

（2）另取5.25g试样加热至失去全部结晶水（杂质不分解），称得质量为3.09g，求Ba(OH)₂·nH₂O中的n值。

使用1∶50比例（角规常数F=1）的角规测定林分每公顷胸高断面积，相割一株相当于每公顷胸高断面积（）。

A.2平方米

B.3平方米

C.4平方米

D.1平方米

在世界贸易范围内全面强制执行的《国际海上危险货物运输规则》，所管理的是世界各国运输的（）。

A.危险货物

B.危险货物包装

C.危险货物及其包装

评价对象