Answer the following question given this paragraph: Dutch elm trees used to be common, beautiful trees in the United States. Now most of them, like this tree, have been killed by Dutch elm disease. Dutch elm disease is caused by a fungus. This is just one example of how fungi can interact with other species. Q: Dutch elm trees used to be common, beautiful trees in the united states. now most of them have been killed by what? Choices: - carbon dioxide - beetles - cancer - dutch elm disease A:
dutch elm disease
(Question)
Answer the following question given this paragraph: When glass breaks, its physical properties change. Instead of one solid sheet of glass, it now has holes and cracks. Q: Which property changes when a glass breaks? Choices: - State - Chemical - density - its physical property A:
(Answer)
its physical property
Ques: Answer the following question given this paragraph: Gilbert Lewis (1875-1946) proposed a third theory of acids and bases that is even more general than either the Arrhenius or Brnsted-Lowry theories. A Lewis acid is a substance that accepts a pair of electrons to form a covalent bond. A Lewis base is a substance that donates a pair of electrons to form a covalent bond. So, a Lewis acid-base reaction is represented by the transfer of a pair of electrons from a base to an acid. A hydrogen ion, which lacks any electrons, accepts a pair of electrons. It is an acid under both the Brnsted-Lowry and Lewis definitions. Ammonia consists of a nitrogen atom as the central atom with a lone pair of electrons. The reaction between ammonia and the hydrogen ion can be depicted as shown in the Figure below . Q: A lewis acid is a substance that accepts a pair of electrons to form what? Choices: - accretion bond - functionality bond - ambivalent bond - covalent bond A:
Ans: covalent bond
(Q).
Answer the following question given this paragraph: Q: The arid environment of a desert, for instance, can quickly deplete an animal of what? Choices: - strength - protein - air - water A:
(A).
water
Ques:Answer the following question given this paragraph: Rivers and streams flow across continents. They cut away at rock, forming river valleys ( Figure below ). These are destructive forces. The bits and pieces of rock carried by rivers are deposited where rivers meet the oceans. These can form deltas, like the Mississippi River delta. They can also form barrier islands, like Padre Island in Texas. Rivers bring sand to the shore, which forms our beaches. These are constructive forces. Q: What type of forces are involved when deposited rock forms deltas or barrier islands? Choices: - gravity forces - accumulation forces - matter forces - constructive forces A:

Ans:constructive forces
Question: Answer the following question given this paragraph: The theory of evolution by natural selection was proposed at about the same time by both Charles Darwin and Alfred Russel Wallace, shown in Figure below , and was set out in detail in Darwin's 1859 book On the Origin of Species . Natural selection is a process that causes heritable traits that are helpful for survival and reproduction to become more common, and harmful traits, or traits that are not helpful or advantageous for survival to become more rare in a population of organisms. This occurs because organisms with advantageous traits are more "fit" to survive in a particular environment and have "adapted" to the conditions of that environment. These individuals will have greater reproductive success than organisms less fit for survival in the environment. This will lead to an increase in the number of organisms with the advantageous trait(s) over time. Over many generations, adaptations occur through a combination of successive, small, random changes in traits, and natural selection of those variants best-suited for their environment. Natural selection is one of the cornerstones of modern biology. Q: What is the method of evolution by which advantageous heritable traits become more common over generations? Choices: - artificial selection - same selection - flow selection - natural selection A:
Answer:
natural selection