一个三角形的三个内角度数的比是1:2:6,这个三角形是锐角三角形.______.

题型:解答题

问题:

一个三角形的三个内角度数的比是1:2:6,这个三角形是锐角三角形.______.

考点:比的应用
题型:解答题

Imagine the situation. You are driving along a desert or on a mountain. You have no idea where you are. You passed the last house two hours ago. Then your car breaks down.   小题1: You have no mobile phone. What should you do? Well, next time take a GPS with you. This invention may be able to help you.   小题2:  It can find your position to within 20 metres. A GPS cannot start your car, but at least you will know where you are.

GPS, which means Global Positioning System, is a small radio receiver. It looks like a mobile phone.  小题3:  We also find GPS devices in cars, planes, or boats. Some of these devices have electronic maps, so you know where you are.   小题4:

Some people think that in the future the GPS will be as common as the mobile.   小题5:  here are also new uses for the GPS. Perhaps they will become like watches. Everyone will have one and you will never be lost again.

A:It is a device(装置) which uses satellites to find the user’s position.

B: For example, in a city they can tell you the name of the street.

C:It is night and it is cold.

D: There are three parts to the Global Positioning System.

E: You can hold it in your hand, or put in your pocket.

F:They are becoming cheaper and more and more accurate(精确的).

题型:解答题

        人们常把飞机比做银燕,其实,飞机是用铝和铝合金做的。纯铝很软,人们在纯铝中加入4%的铜与少量的镁、锰、硅、铁等,制出了硬铝。由于硬铝既保持了铝密度小的特性,又克服了纯铝软的缺点,因此硬铝很快就成了最重要的一种合金。一架普通的飞机,差不多要用50万个硬铝做的铆钉,另外,飞机的外壳、机翼、机尾、螺旋桨、引擎的许多部件也是用硬铝做的。

        在金属的家庭中,由于铝的密度小,使它得天独厚地能随飞机一起腾云驾雾,翱游高空。因此被誉为“会飞的金属”。

        以前,这个“会飞的金属”,还只能飞翔在地球附近的高空,可是从1975年起,随着人造卫星与宇宙火箭一个个接连上天,铝就成了“飞天”的原材料,前苏联第一颗人造卫星的密封外壳与第二颗人造卫星的动物舱,以及球形容器都是铝合金做的。

        本来,铝已经够轻的了,可是1958年以来又研制出了更轻的铝——泡沫铝,在泡沫铝的“肚子里”尽是氢气泡,放在水里,它会像木头一样浮起来,1m3泡沫铝,只有178kg,而1m3的水有1000kg,另外泡沫铝能保温、隔音、不易锈蚀。目前用泡沫铝来做飞机与火箭是最理想的材料。回答下列问题:

(1)铝为什么被誉为“会飞的金属”?

(2)纯铝中加入4%的铜与少量的镁、锰、硅、铁等制成了硬铝,硬铝有哪些优点?

(3)泡沫铝的密度为多少?(写出计算过程)有哪些优点?

题型:解答题

建立科学、明确、有效、可操作性强的加油站用工与分配激励机制和绩效考核体系的目的是()

A.有利于人才的培养和发掘

B.有利于增强企业对员工的凝聚力

C.有利于提高企业的核心竞争力

D.杜绝员工流失现象

题型:解答题

某些电气没备在它们刚退出运行后,残余电荷量可能较大,所以检修或测量前应先放电的设备是()。

A.10kW以下电动机;

B.电缆或电容器;

C.安全灯变压器

D.断路器。

题型:解答题

管理信息系统是集成化系统的概念,要求管理信息系统要有哪项,以指导它的各子系统的实现

A.战略计划

B.总体的系统计划

C.长期计划

D.一体化的数据库

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