... 0.6560μm. Bước sóng dài nhất trong dãy Laiman là 0 ,12 20μm.
Bước sóng dài thứ hai của dãy Laiman là
A. 0 .10 29 μm B. 0 .12 11 m C. 0.0528 μm D. 0 .11 12 μm
Câu 21: Trong thí nghiệm Iâng về giao thoa ánh sáng, ... âm đó là I
0
=10
-12
W/m
2
.Tại 1 điểm A ta đo được mức cường độ âm là L = 70dB.Cường độ âm I
tại A có giá trị là A. 70W/m
2
B. 10
-7
W/m
2
C. 10
7
W/m
2
D. 10
-5
W...
... other ages of history combined.
World population totaled about 500 million in 16 50. It doubled the period from 16 50 -18 50.Today the
population is more than five billion .Estimates based on research ... I came to class at 9.00.Right now it is 10 .00,and I am still in class. I (sit ) at this desk for an
hour. By 9.30,I (sit ) here for a half an hour. By 11 .00,I (sit ) here for two hours...
... d-collaborate
Key 13
Question 1: neat :giản dị và trang nhÃ
1- a 2-c 3-a 4-d 5-a 6-b 7-d 8-b 9-c 10 -a 11 -b 12 -a 13 -d 14 -b 15 -c
Question
Cyclone lốc xoáy farmland :vùng đất
Question 2 (Olympic 23)
1- widespread ... precisely 10 ,if one of your interests is reading, be prepared to 11 about the
sort of books you like 12 ,do not learn all your answers off 13 heart. The inter...
... 5:
1- was walking 2-saw 3-hadnt smiled 4-hadnt seen 5-talked 6-did 7-told 8-found 9-
had been 10 -had got 11 -had had 12 -started 13 -thought 14 -had happened 15 -said 16 -went
17 -would have done 18 -had ... they 10 (get) divorced. It seemed that
he 11 (have) a pretty bad time; but he said that now things 12 (start) to get better. I said I 13 ( often think)
about him, and had w...