The Sun is the sole source of light and heat for the maintenance of life on Earth. It is a star, a glowing ball of gas held together by its own gravity and powered by nuclear fusion at its center. In its physical and chemical properties, the Sun is very similar to most other stars, regardless of when and where they formed. Indeed, our Sun appears to lie right in the middle of the observed ranges of stellar mass, radius, brightness, and composition. Far from detracting from our interest in the Sun, this very mediocrity is one of the main reasons we study itwe can apply our knowledge of solar phenomena to so many other stars in the universe.
a. example
b. explanation c. definition
Question 2
Sociology is a systematic approach to thinking about, studying and understanding society, human social behavior, and social groups. It is different from other approaches to understanding human behavior in two key ways. First, it places its major emphasis on understanding the influences of social groups and the larger society on behavior. In this regard, it is different from psychology, for example, which primarily looks within the individual for explanations of human behavior. Second, sociology does not focus on certain specific areas of human behavior (as, for example, do political science and economics), but rather seeks to explain the broad range of human behavior as it is influenced by social groups and society.
a. explanation
b. cause-effect c. enumeration and definition
Astronaut Piers Sellers during the third spacewalk of STS-121, a demonstration of orbiter heat shiel
Temperature Profile of Earth’s Atmosphere
Intradermal drug administration: (a) cross section of skin showing depth of needle insertion Source:
Intradermal drug administration: (b) the administration site is prepped Source: Pearson Education/PH
Cellular basis of life.
Rural Life