Mark the letter A, B, C, or D on your answer sheet to indicate the underlined part that needs correction in each of the following questions.

The economy of Maine is based to a great extent in its forest, which over 80 percent of its surface area.

A. economy of     

B. to a         

C. in its       

D. percent of

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 36 to 43.

One of the seven wonders of the ancient world, the Great Pyramid of Giza was a monument of wisdom and prophecy built as a tomb for Pharaoh Cheops in 2720 B.C. Despite its antiquity, certain aspects of its construction makes it one of the truly wonders of the world. The thirteen- acre structure near the Nile river is a solid mass of stone blocks covered with limestone. Inside are the number of hidden passageways and the burial chamber of the Pharaoh. It is the largest single structure in the world. The four sides of the pyramid are aligned almost exactly on true north, south, east and west-an incredible engineering feat. The ancient Egyptians were sun worshippers and great astronomers, so computations for the Great Pyramid were based on astronomical observations.

Explorations and detailed examinations of the base of the structure reveal many intersecting lines. Further scientific study indicates that these represent a type of timeline of events - past, present and future. Many of the events have been interpreted and found to coincide with known facts of the past. Others are prophesied for future generations and are currently under investigation. Many believe that pyramids have supernatural powers and this one is no exception. Some researchers even associate it with extraterrestrial beings of ancient past.

        Was this superstructure made by ordinary beings, or one built by a race far superior to any known today?

The word 'feat’ in the first paragraph is closet in meaning to _______.

A. accomplishment        

B. festivity   

C. appendage        

D. structure

X, Y (M_X < M_Y) là 2 axit đều đơn chức, thuộc cùng dãy đồng đẳng; Z là ancol no; T là este hai chức được tạo bởi X, Y và Z (X, Y, Z, T đều mạch hở). Dẫn 28,2 gam hỗn hợp E dạng hơi chứa X, Y, Z, T qua bình đựng 11,5 gam Na (dùng dư), phần khí và hơi thoát ra khỏi bình đem nung nóng có mặt Ni làm xúc tác thấy chúng phản ứng vừa đủ với nhau, thu được một chất hữu cơ duy nhất, đem đốt cháy hợp chất hữu cơ này cần dùng 0,55 mol O₂ thu được 7,2 gam nước. Phần rắn còn lại trong bình đem hòa tan vào nước dư thấy thoát ra 0,05 mol H₂, cô cạn dung dịch sau phản ứng thu được 28,88 gam rắn. Phần trăm khối lượng của Y có trong hỗn hợp E là

A. 11,91%

B. 15,23%

C. 9,08%

D. 18,06%

Đặt z=a+bi

Ta có phần thực a=2\(\sqrt{3}\) ,modun=\(\sqrt{a^2+b^2}\)=10 =>a²+b²=100

<=>12+b²=100 =>b= \(\pm\)\(\sqrt{88}\)

Vậy z=2\(\sqrt{3}\)+\(\sqrt{88}\)i ,z=2\(\sqrt{3}\) -\(\sqrt{88}\)i