皮皮学，免费搜题
登录
搜题
【单选题】
封闭系统经过任意循环过程后,正确的是( )。A.
Q=0
B.
W=0
C.
U=0
D.
Q+W=0
拍照语音搜题，微信中搜索"皮皮学"使用
参考答案：
参考解析：
知识点：
皮皮学刷刷变学霸
举一反三
【简答题】 PPT for this unit
【单选题】According to one survey of 12, 000 people, about 30 percent of those making New Year's resolutions say they don't even keep them into February. And only about 1 in 5 actually stays on track for six mo...
A.
the figure is rather depressing and unexpected as well
B.
those who have made their resolution should give up their effort
C.
whoever keep their resolutions should start eating potato chips
D.
long-term resolutions are not important for those facing troubles
【简答题】果实和蔬菜贮藏时应注意什么
【单选题】According to the instructors in this unit, what is the proper length for making an impromptu speech?
A.
2 minutes
B.
3 minutes
C.
4 minutes
D.
5 minutes
【单选题】关于反平方定律与声强叠加原理的说法有误的是
A.
反平方定律当距离增加一倍时,声强级变化约6dB
B.
反平方定律指R2=2R1,声强级变化约6dB
C.
反平方定律指当点声源在均匀各向同性的媒介传播时产生
D.
声强叠加原理中两台机器可使声强级增加2倍
E.
声强叠加原理中两台机器可使声音能量增加1倍
【单选题】关于叠加原理错误的说法是：
A.
在线弹性或小变形的范围内。
B.
作用在研究对象上荷载个数不限，种类不限。
C.
用叠加原理计算时，不必考虑各荷载作用的先后顺序。
D.
教材中只讲了叠加原理画弯矩图的例子，说明叠加原理只能计算极个别参数;不能计算变形等参数。
【简答题】Please translate the following sentences into Chinese/English. 1. We have obtained your name and address through the Commercial Counselor's Office the Embassy of the People's Republic of China in your...
相关题目：