Mark the letter A, B, C, or D on your answer sheet to show the underlined part that needs correction.
Found in the 12th century, Oxford University ranks among the world’s oldest universities.
Giải chi tiết:
Biogas can be utilized for electricity production, cooking, space heating, water heating and process heating.
Population growth rates vary among regions and even among countries within the same region.
Around 150 B.C. the Greek astronomer Hipparchus developed a system to classify stars according to brightness.