Đặt điện áp xoay chiều u   =   U 0 cos 2 π T t + φ V vào hai đầu đoạn mạch AB như hình bên. Biết R = 2r. Đồ thị biểu diễn điện áp u A N và u M B như hình vẽ bên cạnh. Giá trị U 0 bằng

A. 50 6 V

B. 24 10 V

C.  10 22 V

D.  60 5 V

Trong thí nghiệm Y – âng về giao thoa ánh sáng, hai khe được chiếu bằng ánh sáng đơn sắc có bước sóng λ. Nếu tại điểm M trên màn quan sát có vân tối thứ năm (tính từ vân sáng trung tâm) thì hiệu đường đi của ánh sáng từ hai khe S1,S2 đến M có độ lớn bằng

A. 2λ 

B. 1,5λ

C. 3λ

D. 4,5λ

With

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Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct word for each of the blanks from 46 to 50.

          Vietnamese generally shake hands when greeting and parting. Using both hands shows respect as does a (46) _______ bow of the head. In rural areas, elderly people who do not extend their hand are greeted with a slight bow. Women are more likely to bow the head than to shake hands. Vietnamese names begin with the family name and are (47) _______ by a given name. People address one another by their given names, but add a title that indicates their perceived relationship to the other person. These titles are family related rather than professional. Among colleagues, for example, the younger of the two might combine the given name with the title of “Anh” (Older Brother). A/n (48) _______ greeting combined with the given name and title is “Xin chao” (Hello). Classifiers for gender and familiarity are also combined with the greeting. In formal meetings, business cards are sometimes exchanged on greeting.
          Vietnamese have a strong (49) _______ of hospitality and feel embarrassed if they cannot show their guests full respect by preparing for their arrival. Therefore, it is (50) _______ to visit someone without having been invited. Gifts are not required, but are appreciated. Flowers, incense, or tea may be appropriate gifts for the hosts. Hosts also appreciate a small gift for their children or elderly parents

Điền vào số (46)

A. light       

B. slight      

C. lightly     

D. lighted

Today, the television is an indispensable item and is present in most families, from
Urban to rural. It is a means of transmitting information that is monitored by many people
The most and is the spiritual food of a large section of the population with many waves and chapters
The television is becoming more and more attractive.
To create a TV with many smart features today, there is a contribution
Of many scientists in many different generations. The television went through a broadcast process
It lasted from the 1920s to the present day.

Có các dung dịch riêng biệt sau: NaCl, AgNO₃, Pb(NO₃)₂, NH₄NO₃, ZnCl₂,CaCl₂, CuSO₄, FeCl₂. Khi sục khí H₂S vào các dung dịch trên, số trường hợp sinh ra kết tủa là:

A. 6.

B. 5.

C. 3.

D. 4.

Family feelings are not only visible through speech but specific actions that you feel sacred and can show up right at our main meal. For many simple meals are to eat rice, talk to family members. But for the body the meal is sentimental in every heart of every family member marked. The feelings of grandparents, parents, or conditions are linked together.
Family dinner is as simple as the meals of other families. But mode will be the same that that is that that is.