Tham khảo tài liệu 'economic english 4', ngoại ngữ, anh ngữ phổ thông phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | THE GED SCIENCE EXAM 5. Isomers are molecules that have the same number of the same elements but in a different arrangement. Which one of the following is an isomer of 2-propanol shown below which contains Carbon C Hydrogen H and Oxygen O H OH H i I i H-C-C-C-H .1. .1. .1. H H H a. H OH H H 1 1 1 1 H-C-C-C-C-H .1. .1. .1. .1. H H H H b. H H H 1 1 1 H-C-C-C-OH .1. .1. .1. H H H c. H H I I H-C-C-OH .1. .1. H H d. H OH I i H-C-C-H .1. .1. H H e. H H H 1 1 1 H-C-C-C-H .1. .1. .1. H H H Questions 6 and 7 are based on the following passage. The rectilinear propagation of light and the law of reflection had been observed long before the development of modern theories that correctly explain these observations. Rectilinear propagation of light refers to the fact that light travels in straight lines. Hero of Alexandria who lived around the first century explained these observations by stating that light travels along the shortest allowed path. It wasn t until 1657 that Pierre de Fermat rejected Hero s shortest-path theory and showed that light propagates along the path taking the least time. From his principle of least time Fermat re-derived the law of reflection as well as the law of refraction. This principle played an important role in the development of quantum mechanics. 6. The passage shows that a. reflection and refraction can t be explained by the same theory. b. the term reflection means that light travels in straight lines. c. Hero of Alexandria had insight into quantum mechanics. d. scientists develop theories to explain the phenomena they observe in nature. e. light travels along the shortest allowed path. 7. Which general statement about science is NOT supported by the passage a. A scientific finding sometimes plays a role in other scientific findings. b. Centuries can pass before an observation is correctly explained by science. c. Theory should not be based on experimental evidence. d. Different scientists do not always come up with the same explanation for an
