Ques: Q: What does a theory need to be supported by? Read this paragraph and choose the correct option from the provided answers: In science, a theory has been repeatedly shown to be true. A theory is supported by many observations. However, a theory may be disproved if conflicting data is discovered. Many important theories have been shown to be true by many observations and experiments and are extremely unlikely to be disproved. These include the theory of plate tectonics and the theory of evolution. Choices: - facts - peer reviewed journals - scientists - many observations A:
Ans: many observations

Ques: Q: In many species, display behaviors, like a gorilla beating on its chest, are used instead of actual physical attacks to show what? Read this paragraph and choose the correct option from the provided answers: In many species, display behaviorsrather than actual physical attacksare used to show aggression. This helps prevent injury and death. Male gorillas, for example, are more likely to put on a display of aggression than to attack another male. In fact, gorillas have a whole series of display behaviors that they use to show aggression. They beat on their chest, dash back and forth, and pound the ground with their hands. Choices: - dominance - friction - stress - aggression A:
Ans: aggression

Ques: Q: What happens when heated water is released into a body of water? Read this paragraph and choose the correct option from the provided answers: If heated water is released into a body of water, it may cause thermal pollution. Thermal pollution is a reduction in the quality of water because of an increase in water temperature. A common cause of thermal pollution is the use of water as a coolant by power plants and factories. This water is heated and then returned to the natural environment at a higher temperature. Choices: - crystalline pollution - gaseous pollution - geysers - thermal pollution A:
Ans: thermal pollution

Ques: Q: What gas comprises about three-fourths of earth's atmosphere? Read this paragraph and choose the correct option from the provided answers: Nitrogen is another common element found in living things. It is needed to form both proteins and nucleic acids such as DNA. Nitrogen gas makes up 78 percent of Earth's atmosphere. In the nitrogen cycle, nitrogen flows back and forth between the atmosphere and living things. You can see how it happens in Figure below . Several different types of bacteria play major roles in the cycle. Choices: - hydrogen - carbon dioxide - oxygen - nitrogen A:
Ans:
nitrogen