[单选题]优级纯化学试剂的标签为红色。（ ）[1.0分]
A. 正确
B. 错误

[单选题](466817)机械天平是根据( )原理设计。(1.0分)
A.平衡
B.稳定
C.杠杆
D.等臂

[判断题]《煤矿防治水规定》中规定的重大突水事故是指突水量首次达到300m3/h以上或者造成死亡3人以上等突水事故。（0.08分）
A.正确
B.错误

[单项选择]关于肾结核患者的尿液，叙述错误的是（）.
A. 一般呈酸性反应
B. 有较多红细胞和白细胞
C. 尿沉淀涂片抗酸染色50%～70%的病例可查到结核杆菌
D. 抗酸染色以清晨第一次排尿的阳性率最高
E. 若查到抗酸杆菌即可诊断肾结核

[单选题]移动电气设备时，必须经安全员切断电源并作妥善处理后进行。(　　)
A.正确
B.错误

[多选题]触电急救必须在（ ）才能去施救。
A.A.触电时;
B.B.断电后;
C.C.确认无电时;
D.D.送电后

[单选题]BC003 鼓风机的( )起着集气作用,所以又称为集流器。
A.机壳
B.吸入口
C.叶轮
D.排出口

[单项选择]砌筑工程冬期施工方法中，掺盐砂浆法中常用的外加剂为（）等盐类。
A. 氯盐或亚硝酸钠
B. 氯化钠和氯化钙
C. 氯盐及FDN
D. 氯盐及减气剂

[判断题]载客列车经过辅助线时限速20km/h。
A.正确
B.错误

[单项选择]葡萄球菌肺炎，胸部X线显示肺段或肺叶实变可形成空洞或液气囊腔，另一特征为（）
A. 支气管充气征
B. X线阴影的易变性
C. 大片阴影
D. 肺纹理增粗
E. 肺叶稍模糊

[单项选择]“唯上智与下想不移”、“中而知之”等反映了影响人的发展因素的哪一理论（）。
A. 环境决定论
B. 遗传决定论
C. 教育万能论
D. 儿童学理论

[单项选择]Music comes in many forms; most countries have a style of their own. (1) the turn of the last century when jazz was born, America had no prominent (2) of its own. No one knows exactly when jazz was (3) , or by whom. But it began to be (4) in the early 1900s Jazz is American’s contri- bution to (5) music. In contrast (6) classical music, which (7) formal Euro- pean traditions, jazz is spontaneous and flee-form. It bubbles with (8) , expressing the moods, interests, and emotions of the people. In the 1920s jazz sounded like American, and (9) it does today. The origins of this music are as (10) as the music itself. American Negroes, or blacks, as they are called today, were the jazz (11) . They were brought to Southern States (12) slaves. They were sold to plantation owners and (13) to work long hours. When a Negro died his friend and relatives (
A. demonstrated
B. composed
C. hosted
D. formed