1. Which of the following best summarized the main idea of the passage? <span>A. “Researchers use wind tunnels to learn more about how an aircraft will fly.” (paragraph 1)
</span>2. Which key detail helps the reader understand the importance of using wind tunnels? <span> </span><span>B. Wind tunnels are design tools that help make safer aircraft vehicles. </span> 3. The statement that “NASA also works with others that need to use wind tunnels” most strongly suggests that <span>D. Many companies do not have their own wind tunnels </span> 4. The most important feature of a wind tunnel used to test vehicles that can land on Mars is the ability to test how <span>B. A thin atmosphere affects vehicles </span> 5. Which sentence from the passage best explains why NASA uses wind tunnels to test spacecraft models? <span>B. “Spacecraft and rockets have to travel through the atmosphere to get to space.” (paragraph 5) </span> 6. Which sentence from the passage best explains how a wind tunnel works? <span>C. “The air moving around the still object shows what would happen if the object were moving through the air.” (paragraph 2) </span>