Khi dùng một thấu kính hội tụ tiêu cự f làm kính lúp để nhìn một vật, ta phải đặt vật cách thấu kính một khoảng

Chia sẻ

Một số câu hỏi khác có thể bạn quan tâm.

• Choose one sentence that has the same meaning as the root one:

  I have no ability to sing and play any musical instrument.
  
  

• Choose the best answer for the following sentence:

  The nurse suggested ___________ two aspirins.
   

• Choose one sentence that has the same meaning as the root one:

  This is the first time I meet such a beautiful shell.
  
  

• Choose one sentence that has the same meaning as the root one:

  The school and the neighboring pub were destroyed by the explosion.
  
  

• Choose the best answer for the following sentence:

  ___________ do the volunteers often do?
  
  

• Choose the best answer for the following sentence:

  Do volunteers often spend time ______________ other people in hospitals, orphanages or homes for the aged?
   

• Choose the best answer for the following sentence:

  ____________ young volunteers do the work, such as: cleaning up the houses, doing the shopping and cooking meals for the sick and old people?
  
   

• Choose the best answer for the following sentence:

  Do you think that if you bring __________ to others, you are also a happy person?
   

• Choose the correct sentence which is built from the words and phrases given:

   I / display / my collection of dolls / in a window / arrange them / size
  
  

• Choose the correct sentence which is built from the words and phrases given:

  energy / electricity / can / of / heat / other / be / and / solar / forms / into / as / energy / converted / such