【单选题】The second season of A Bite of China ________ for a month. It turns out to be the most popular documentary.
【简答题】指出下列方程在空间代表什么曲面,若是旋转曲面,则指出它们是由什么曲线绕什么轴旋转而产生的. (1)x 2 +y 2 +z 2 +2z=3; (2)x 2 =4z (3)x 2 -y 2 =0, (4)x 2 -y 2 =4z.
【判断题】钢轨类型习惯上用每米大致质量的kg整数(kg/m)表示。()
【多选题】餐巾环也称为餐巾扣 , 有 ( ) 的等。
【简答题】(1)下列曲线分别表示元素的某种性质与核电荷数的关系(Z为核电荷数,Y为元素的有关性质)。请把与下面元素有关性质相符的曲线标号(a、b、c、d)填入相应的空格中 ①ⅡA族元素的最外层电子数_____________。 ②第3周期元素的最高化合价_____________。 ③F - 、Na + 、Mg 2+ 、Al 3+ 的离子半径_____________。 (2)元素X、Y、Z、M、N均为短周...
【简答题】Unless otherwise stipulated in the Credit,the minimum amount for which the insurance document must indicate the insurance cover to have been effected is the CIF[cost,insurance and freight(...“named po...
【简答题】(13分) (1)(3分)下列曲线分别表示元素的某种性质与核电荷数的关系(Z为核电荷数,Y为元素的有关性质)。请把与下面元素有关性质相符的曲线标号(a、b、c、d)填入相应的空格中: ①ⅡA族元素的最外层电子数 ▲ 。 ②第3周期元素的最高化合价 ▲ 。 ③F - 、 Na + 、Mg 2+ 、Al 3+ 的离子半径 ▲ 。 (2)(10分)元素X、Y、Z、M、N均为短周期主族元素,且原子序数依...
【单选题】From the passage we can know patients in hospital ______.
A.
can't carry their medical documents to the hospital.
B.
must arrange their relatives or friends to help them for clothes.
C.
should have all their meals.
D.
can phone only one of their relatives or friends one day.