Cho mạch có 3 điện trở mắc nối tiếp lần lượt là 2 Ω, 3 Ω và 4Ω với nguồn điện 10 V, điện trở trong 1 Ω. Hiệu điện thế 2 đầu nguồn điện l

A. 9 V

B. 10 V

C. 1 V

D. 8 V

Read the following passage and mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the questions from 35 to 42.

Washington was the first city in history to be created solely for the purpose of governance. Following the Revolution, members of Congress had hotly debated the question of a permanent home for themselves and for those departments – the Treasury, the Patent Office and so on – which even the sketchiest of central governments would feel obliged to establish. In 1790, largely in order to put an end to congressional bickering, George Washington was charged with selecting a site for the newly designated federal district. Not much to anyone’s surprise but to the disappointment of many he chose a tract of land on the banks of the Potomac River, a few miles upstream from his beloved plantation Mount Vernon.

The District of Columbia was taken in part from Virginia and in part from Maryland. At the time it was laid out, its hundred square miles consisted of gently rolling hills, some under cultivation and the rest heavily wooded, with a number of creeks and much swampy land along the Potomac. There is now a section of Washington that is commonly referred to as Foggy Bottom; that section bore the same nickname a hundred and eighty years ago.

Two ports cities, Alexandria and Georgetown, flourished within sight of the new capital and gave it access by ship to the most important cities of the infant nation – Charleston, Baltimore, Philadelphia, New York, Newport, Salem and Portsmouth – and also to the far-off ports of England and the Continent.

It can be referred from the passage that the term “Foggy Bottom” in the second paragraph refers to a section of Washington. D. C that______.

A. used to be mostly swampland

B. lies at the bottom of Mount Vernon

C. has the lowest population in the district

D. used to be the site of the national weather station

Có bao nhiêu nguyên tố hóa học mà nguyên tử của nó có cấu hình electron lớp ngoài cùng là 4s¹

A. 2

B. 12

C. 3

D. 1