渗透检测可发现铸件表面的（）缺陷。 A.气孔 B.裂纹 C.冷隔、夹杂 D.以上都是

（9分）25℃时，有0.01 mol•L^-1的醋酸溶液，试回答下列问题：

（1）写出醋酸的电离平衡常数表达式

（2）达平衡时，溶液中氢离子浓度是多少?（25℃时，醋酸的电离平衡常数为1. 75×10 ^-5）

（3）当向该溶液中加入一定量的盐酸时，溶液中的c(H⁺)、c (CH₃COO^-)、c (CH₃COOH) 是否又发生变化? 电离常数是否发生变化? 为什么 ?

对员工工作的考核与评估可以采用如下方法（）。

A.从上到下的考核

B.同级之间互相考核

C.员工自我考核

D.从下而上的考核

冻疮症见时时寒战，四肢厥冷，感觉麻木，意识模糊，蜷卧嗜睡，呼吸微弱，甚至神志不清，舌淡紫苔白，脉微欲绝。内治方剂宜选用（）

A.当归四逆汤

B.四逆加人参汤

C.四妙勇安汤

D.人参养荣汤

E.阳和汤

公安消防部队在参与重大灾害事故应急救援中，一级个人防护为（）。

A、全身、封闭式防化服、全棉防静电内外衣、正压式空气呼吸器或全防型滤毒罐

B、全身、内置式重型防化服、全棉防静电内外衣、正压式空气呼吸器或全防型滤毒罐

C、全身、简易防化服、全棉防静电内外衣、正压式空气呼吸器或全防型滤毒罐

D、呼吸、简易防化服、战斗服、简易滤毒罐、面罩或口罩、毛巾等防护器材

There has been much speculation about the origin of baseball. In 1907 a special commission decided that the modern game was invented by Abner Doubleday in 1839. One hundred years later the National Baseball Museum was opened to honor Doubleday. Historians, however, disagree about the origin of baseball. Some say that baseball comes from bat-and-ball games of ancient times. It is a matter of record that in the 1700s English boys played a game they called "baseball". Americans have played a kind of baseball since about 1800. At first the American game had different rules and different names in various parts of the country — "town ball", "rounders", or "one old cat". Youngsters today still play some of these simplified forms of the game.Baseball did not receive a standard set of rules until 1845, when Alexander Cartwright organized the Knickerbocker Baseball Club of New York City. The rules Cartwright set up for his nine-player team were widely adopted by other clubs and formed the basis of modern baseball. The game was played on a "diamond" infield with the bases 90 feet apart. The first team to score 21 runs was declared the winner. By 1858 the National Association of Baseball Players was formed with 25 amateur teams. The Cincinnati Red Stockings began to pay players in 1869.

What was the first professional baseball team called

A．New York Knickerbockers.

B．Milwaukee Braves.

C．Cincinnati Red Stockings.

D．Brooklyn Dodgers.