【单选题】电池箱内有四个蓄电池,正极与正极相连,负极与负极相连。蓄电池的开路电压和内阻分别为12.2V和0.5欧姆,12.1V和0.1欧姆,12.4V和0.16欧姆,12V和0.2欧姆。则电池箱的戴维宁等效电源电动势为_____,戴维宁等效电阻为______。
【单选题】Passage 2--- Question 55. What does the author suggest businesses and the government do?--- (Para. 1) Imagine you enter a car with no steering wheel, no brake or accelerator pedals (踏板).Under a voice-...
A.
Keep pace with technological developments.
B.
Make new technologies affordable to everyone.
C.
Enable everyone to benefit from new technologies.
D.
Popularize the use of new technologies and devices.
【简答题】1 Lunch break at the hotdog stand in the park is the most e__________ and interesting time of day for me.
【多选题】在带领旅游者到大型娱乐场所游玩时,地陪应做好的工作有( )。
【单选题】Passage 2--- Question 52. How would the elderly and the disabled benefit from driverless cars?--- (Para. 1) Imagine you enter a car with no steering wheel, no brake or accelerator pedals (踏板).Under a ...
A.
They could enjoy greater mobility.
B.
They would have no trouble driving.
C.
They would suffer no road accidents.
D.
They could go anywhere they want.
【单选题】u =- 100 cos ( 6 π t + 10 ° ) V 超前 i = 5cos ( 6 π t - 15 ° ) A 的相位差是