Polime được trùng hợp từ etilen. Hỏi 280 gam polietilen đã được trùng hợp từ tối thiểu bao nhiêu phân tử etilen?
A.$ 3,{{01.10}^{24}} $
B.$ {{10}^{23}} $
C.$ 6,{{02.10}^{23}} $
D.$ 6,{{02.10}^{24}} $

Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to the following question.
My sister won her ………………… to Harvard for her activities outside her school.
A.fee
B.scholarship
C.grant
D.tuition

Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to the following question.
Technology has its ………., like separating people and allowing hackers to steal information.
A.strengths
B.advantages
C.pros
D.drawbacks

Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to the following question.
………. are professionals who save people by performing operations.
A.surgeons
B.housewives
C.nurses
D.carers

Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to the following question.
Many _____ organizations exist to help disadvantaged people for free.
A.non-government
B.non-profit
C.non-use
D.non-money

Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to the following question.
Smartphones are great but they also ………. a lot of risks.
A.risk
B.entail
C.do
D.capture

Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to the following question.
Our ………. is where people meet every Sunday to listen to the priest preaching.
A.grave
B.church
C.playground
D.garage

Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to the following question.
The ………. is in charge of many campaigns against corruption.
A.street
B.human
C.corruptible
D.government

Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to the following question.
We object to kids having band ………… . Gangs are prohibited here.
A.devotion
B.promotion
C.advocation
D.affiliation

Cho biết nguyên tử N có số đơn vị điện tích hạt nhân là 7. Kết luận nào sau đây là đúng?
A.Nguyên tử N có số khối là 7.
B.Nguyên tử N có điện tích hạt nhân là 7.
C.Nguyên tử N có số nơtron là 14.
D.Nguyên tử N có 7 proton.