Rocks which have solidified directly
from molten materials are called igneous rocks. Igneous rocks are commonly
referred to as primary rocks because they are the original source of material
found in sedimentaries and metamorphics. Igneous rocks compose the greater part
of the earth’s crust, but they are generally covered at the surface by a
relatively thin layer of sedimentary or metamorphic rocks. Igneous rocks are
distinguished by the following characteristics: (1) they contain no fossils; (2)
they have no regular arrangement of layers; and (3) they are nearly always made
up of crystals. Sedimentary rocks are composed largely of minute fragments derived from the disintegration of existing rocks and in some instances from the remains of animals. As sediments are transported, individual fragments are assorted according to size. Distinct layers of such sed A. strata B. limestone C. metamorphic rock D. no trace of fossils [单选题]高压电气设备倒闸操作一般应由( )填用配电倒闸操作票(见附录J,以下简称操作票)。每份操作票只能用于一个操作任务。
A.操作人员 B.工作负责人 C.工作监护人 D.检修人员 [单项选择]某男,50岁,右踝关节疼痛20天,患者20天前感冒后出现右踝关节剧烈疼痛,疼痛多在夜间发作,呈间歇性,影响睡眠。查:右踝关节有红、肿、热、痛。其余关节无异常。患者有高血压、糖尿病病史该病的发病原因是由于()
A. 血中尿酸增高 B. 甲状腺功能亢进 C. 缺钙 D. 维生素缺乏 E. 肾衰竭 [单选题]战斗员要按照各自的( ),负责保管好消防器材和个人装备。
A.要求 B.职责 C.任务 D.分工 [单项选择]在电容器串联时()。
A. 每个电容所带的电量相等 B. 每个电容上的电压相等 C. 每个电容所带的电量不等 D. 每个电容上的电压与电容成正比 [单项选择]张某,男,45岁,胁肋胀痛,口苦口黏,胸闷纳呆,恶心呕吐,小便黄赤,大便不爽,舌红苔黄腻,脉弦滑数。治疗宜选方()
A. 芍药甘草汤 B. 龙胆泻肝汤 C. 复元活血汤 D. 柴胡疏肝散 E. 玉女煎 [判断题]多家单位共用天窗作业签认的顺序为主体单位、共用单位、配合单位、设备管理单位、车站行车人员。
A.正确 B.错误 [单选题]442.(294804)系统只有( )系统管理员,系统维护员和系统监视员有( )。(1.0分)
A.A、1个,多个 B.B、1个,各1个 C.C、多个,多个 D.D、多个,1个 [单选题]KP-2A控制箱过压保护回路的作用是,当发电机失控造成电压过高时,自动切断( ),使发电机停止供电,以保护发电机及用电器。
A.直流输出电路 B.三相整流电路 C.激磁回路 D.测量回路 [单选题]列车运行中,遇昼间展开的()信号旗,司机需将列车降低到要求的速度。
A.红色 B.黄色 C.绿色 [单选题]平行不对中主要引起( )振动。
A.径向和轴向 B.轴向 C.径向 D.以上说法都不对 我来回答: 提交
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