【简答题】Writing: Suppose you are a close friend of the Elliott family. Write a letter of condolence(吊唁) to Pauline on the death of Frank. Write a letter of about 130 words.
【简答题】Write a letter of condolence to the patients in Wuhan hospitals with about 150 words.
【单选题】灯具在空间各个方向上的光强的分布情况用()来描述。
【简答题】A)They are talking about an advertisement. B) They are talking about an interview. C)They are talking about the time for the interview. D)They are talking about the interviewees.
【单选题】What are they talking about?
A.
They are talking about the man's vacation.
B.
They are talking about their vacation plans.
C.
They are talking about the weather.
【单选题】My mobile phone disappeared. Where _____ I have left it?
【简答题】(1)Write the possible values of l when n=5. (2)Write the allowed number of orbitals (a) with the quantum numbers n=4,l=3;(b) with the quantum numbers n=4;(c) with the quantum numbers n=7,l=6,m=6;(d) w...
【多选题】平行单色光垂直入射到平面衍射光栅上,下列说法正确的是:
A.
若增大光栅常数,则衍射图样中明条纹的间距将变大
B.
若增大光栅常数,则衍射图样中明条纹的间距将变小