Answer the following question given this paragraph: The ion concentration of neutral, pure water gives water a pH of 7 and sets the standard for defining acids and bases. Acids have a pH lower than 7, and bases have a pH higher than 7. Q: What is the ph level of neutral, pure water? Choices: - six and a half - five - six - seven A:
seven
(Question)
Answer the following question given this paragraph: 11.2 Mechanisms of Evolution There are four factors that can change the allele frequencies of a population. Natural selection works by selecting for alleles that confer beneficial traits or behaviors, while selecting against those for deleterious qualities. Mutations introduce new alleles into a population. Genetic drift stems from the chance occurrence that some individuals have more offspring than others and results in changes in allele frequencies that are random in direction. When individuals leave or join the population, allele frequencies can change as a result of gene flow. Q: Out of the four ways that allele frequencies of a population can be changed, which way is caused by individuals leaving or joining the population? Choices: - Allopatric speciation - spontaneous mutation - mass extinction - gene flow A:
(Answer)
gene flow
Ques: Answer the following question given this paragraph: Both dry and wet cells work the same basic way. The electrodes react chemically with the electrolyte, causing one electrode to give up electrons and the other electrode to accept electrons. In the case of zinc and carbon electrodes, the zinc electrode attracts electrons and becomes negatively charged, while the carbon electrode gives up electrons and becomes positively charged. Electrons flow through the electrolyte from the negative to positive electrode. If wires are used to connect the two electrodes at their terminal ends, electric current will flow through the wires and can be used to power a light bulb or other electric device. Q: Electrons flow through the electrolyte from the ________ to __________ electrode. Choices: - neutral; negative - negative; neutral - positive; negative - negative; positive A:
Ans: negative; positive
(Q).
Answer the following question given this paragraph: Reptiles cold-blooded, or ectothermic, meaning that their heat come from their environment. Sometimes defined as all amniotes that are not birds or mammals. Reptiles can be classified by skull structure into four groups: . Q: What term given to animals like reptiles is a synonym for ectothermic, which means that their heat comes from their environment? Choices: - warm-blooded - hot-blooded - thermal regulating - cold-blooded A:
(A).
cold-blooded
Ques:Answer the following question given this paragraph: Q: What can lead to a loss of genetic variation within populations? Choices: - migration - adaptation - natural selection - genetic drift A:

Ans:genetic drift
Ques:Answer the following question given this paragraph: The major cause of outdoor air pollution is the burning of fossil fuels. Fossil fuels are burned in power plants, factories, motor vehicles, and home heating systems. Ranching and using chemicals such as fertilizers also cause outdoor air pollution. Erosion of soil in farm fields, mining activities, and construction sites adds dust particles to the air as well. Some specific outdoor air pollutants are described in Table below . Q: What is the major cause of outdoor air pollution? Choices: - electric lines - agricultural equipment - manufacturing industry - burning fossil fuels A:

Ans:
burning fossil fuels