【单选题】木制案板具有光滑、表面平整和()等特点。
【简答题】My father raged at my ______________________
【单选题】关于环境气体对果蔬呼吸作用影响的说法不正确的是( )
A.
在环境气体成分中,二氧化碳和由果实释放出来的乙烯对果蔬的呼吸作用有重大影响
B.
适当降低储藏环境中的氧浓度和适当提高二氧化碳浓度,可以抑制果蔬的呼吸作用,从而延缓果蔬的后熟、衰老过程
C.
较低温度和低氧、高二氧化碳也会抑制果蔬乙烯的合成并抑制已有乙烯对果蔬的影响
D.
较低温度和低氧、高氮气也会抑制果蔬乙烯的合成并抑制已有乙烯对果蔬的影响
【单选题】一半径为R的“无限长”圆柱形带电体,其电荷体密度 =Ar(r R),式中A为常数.圆柱体内,外各点场强大小分别是______,选距离轴线的距离为 l ( l > R)处为电势零点,圆柱体内、外各点的电势大小分别是______.
【单选题】—Father's Day is coming. I'm going back home.to see my father. —___________. [ ]
A.
Give my best wishes to him
C.
Say goodbye to him, please
【单选题】What is the definition of translation given by the professor?
A.
It is using common sense to say something simply.
B.
It is rendering the meaning of a text into another language.
C.
It is a complicated and artificial process to describe facts.
D.
It is an activity the translator pretends to be someone els
【简答题】一半径为R的“无限长”圆柱形带电体,其电荷体密度为 ,式中A为常量.试求: 圆柱体内、外各点场强大小分布;
【单选题】—Are those _____ pants? —No, they are _____. [ ]