A.Nghiên cứu sinh.
B.Phi hành gia.
C.Nhà khoa học
D.Nhà phát minh.

A.thế giới tự nhiên.
B.những ứng dụng khoa học tự nhiên trong cuộc sống.
C.những thành tựu của khoa học tự nhiên.
D.thế giới tự nhiên và nhũng ứng dụng khoa học tự nhiên trong cuộc sống.

A.\(k\dfrac{{\lambda D}}{a}\) với \(k = 0;\,\, \pm 1;\,\, \pm 2;...\)
B.\(\left( {k + 0,5} \right)\dfrac{{\lambda D}}{a}\) với \(k = 0;\,\, \pm 1;\,\, \pm 2;...\)
C.\(\left( {k + 0,5} \right)\dfrac{{aD}}{\lambda }\) với \(k = 0;\,\, \pm 1;\,\, \pm 2;...\)
D.\(k\dfrac{{aD}}{\lambda }\) với \(k = 0;\,\, \pm 1;\,\, \pm 2;...\)

A.Sử dụng những hình thức đấu tranh công khai, hợp pháp.
B.Có sự tham gia của một bộ phận người Pháp tiến bộ.
C.Thực hiện khẩu hiệu chống phát xít, chống chiến tranh.
D.Chống lại một bộ phận thực dân Pháp ở Đông Dương.

A.1617
B.1616
C.1600
D.1671

A.Provided he were an expert on computer technology, he would invest in some computer companies.
B.He wishes he was investing in some computer companies now.
C.Had he been an expert on computer technology, he would invest in some computer companies now.
D.If he had been an expert on computer technology, he would have invested in some computer companies.

A.Provided he were an expert on computer technology, he would invest in some computer companies.
B.He wishes he was investing in some computer companies now.
C.Had he been an expert on computer technology, he would invest in some computer companies now.
D.If he had been an expert on computer technology, he would have invested in some computer companies.

A.Had it not been for TV news programs, people wouldn’t have been better informed.
B.Never have people been so well informed as they are now, thanks to TV news programs.
C.Not until people had been well informed was TV news programs more informative.
D.No sooner had TV news programs been informative than people were better informed.

A.Positive changes in American schools
B.Valuable academic learning experiences
C.Field trips for schoolchildren
D.New trends in educational development

A.Positive changes in American schools
B.Valuable academic learning experiences
C.Field trips for schoolchildren
D.New trends in educational development