Answer: The answers are indeed:
15) A - To explain how seaplanes are used.
16) D - The author gives specific examples of how coast guards, fire fighters, and airlines use seaplanes.
17) C - leaders
18) D - To describe the different types of seaplanes
Explanation:
Why did the author write this passage? --> The author explains that seaplanes may have specific uses that regular planes do not have, such as rescuing people in the ocean or traveling to islands where there are no airports. From such an introduction, he explains how they can be used to do so: by being built in a way that they can land on and take off from water.
How does the author support the idea of the current usefulness of seaplanes? - Again, by informing the readers of the uses of the seaplanes in rescuing, putting out fires, and flying people to remote areas.
According to the passage, the word officials means - leaders. We can reach that conclusion from the context 'In World War II, military officials used seaplanes for a number of important tasks.' The best option to substitute the word "officials" in this sentence is "leaders".
Which best describes the purpose of paragraph 2? - The second paragraph talks about the three different types of seaplanes: the flying boats, the floatplanes, and the amphibious ones. The differences between each type - their appearance and fuselage - are explained.
