【单选题】Hydropower facilities in the Himalaya are mentioned in the passage to show that __________
A.
those facilities are outdated
B.
they are equipped with advanced technologies
C.
climate change has some negative influence on them
D.
they should be maintained carefully due to their location
【判断题】制造业的本质是从自然界直接撮所需要的物品。
【简答题】听力原文:Welcome to our series on renewable resources. The topic today is hydropower. As you most probably know, 'hydro' means water—so we are talking about using water to generate electricity. Of course,...
【简答题】已知:直线AB和点C的投影,且水平线DC⊥AB,DC长40mm(图2-5a)。 求作:线段DC的投影。
【单选题】The natural resources, such as mine, forest, and hydropower (水电) in that area have been ________. [ ]
【简答题】如图,在菱形ABCD中,∠A=60°, =4,O为对角线BD的中点,过O点作OE⊥AB,垂足为E. (1)求∠ABD 的度数; (2)求线段 的长.
【简答题】过点P(2,1)作抛物线y 2 =4x的弦AB,若弦恰被P点平分, (1)求直线AB所在直线方程;(用一般式表示) (2)求弦长|AB|。
【简答题】如图,AB是⊙ 的直径,弦CD与AB交于点E,过点 作⊙ 的切线与 的延长线交于点 ,如果 , , 为 的中点. (1)求证: ; (2)求AB的长.