ở một loài thực vật, tính trạng màu sắc của hoa do 1 cặp gen quy định

a) Dùng các chữ cái để quy ước cho tính trạng này biết màu sắc của hoa có 2 trạng thái cơ bản: màu hoa đỏ(tính trạng trội) và màu hoa trắng(tính trạng lặn)

b) nếu cho các cây chứa tính trạng trên tự thụ phấn thì có bao nhiêu kiểu tự thụ của cặp tính trạng trên? Viết sơ đồ lai minh họa

1.A

2.B

3.B

4.C

5.B

My neighborhood is famous for good and cheap restaurants

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 30 to 37.

        The Roman alphabet took thousands of years to develop, from the picture writing of the ancient Egyptians through modifications by Phoenicians, Greek, Romans, and others. Yet in just a dozen years, one man, Sequoyah, invented an alphabet for the Cherokee people. Bom in eastern Tennessee, Sequoyah was a hunter and a silversmith in his youth, as well as an able interpreter who knew Spanish, French and English.

        Sequoyah wanted his people to have the secret of the “talking leaves” as he called his books of white people, and so he set out to design a written form of Cherokee. His chief aim was to record his people’s ancient tribal customs. He began by designing pictographs for every word in the Cherokee vocabulary. Reputedly his wife, angry with him for his neglect of garden and house, burned his notes, and he had to start over. This time, having concluded that picture-writing was cumbersome, he made symbols for the sounds of Cherokee language. Eventually he refined his system to eighty-five characters, which he borrowed from the Roman, Greek, and Hebrew alphabets. He presented this system to the Cherokee General Council in 1821, and it was wholeheartedly approved. The response was phenomenal. Cherokees who had stmggled for months to leam English lettering school picked up the new system in days. Several books were printed in Cherokee, and in 1828, a newspaper, the Cherokee Phoenix, was first published in the new alphabet. Sequoyah was acclaimed by his people.

         In his later life, Sequoyah dedicated himself to the general advancement of his people. He went to Washington, D.C, as a representative of the Western tribes. He helped settled bitter differences among Cherokee after their forced movement by the federal government to the Oklahoma territory in the 1930s. He died in Mexico in 1843 while searching for groups of lost Cherokee. A statue of Sequoyah represents Oklahoma in the Statuary Hall in the Capitol building of Washington, DC. However, he is probably chiefly remembered today because Sequoias, the giant redwood trees of California, are named of him.

All of the following were mentioned in the passage as alphabet systems that Squoyah borrowed from EXCEPT________.

A. Egyptian

B. Hebrew

C. Roman

D. Greek

Đốt cháy hoàn toàn m gam hỗn hợp X gồm metyl fomat, axit axetic trong O₂. Hấp thụ hết sản phẩm cháy qua bình đựng dung dịch Ca(OH)₂ dư, thấy tạo ra 10 gam kết tủa. Giá trị của m là:

A. 3,0

B. 2,0

C. 4,0

D. 6,0