F Three of today’s largest telescopes—Gemini North, Sub…
F Three of today’s largest telescopes—Gemini North, Subaru, and Keck—stand within hailing distance of one another atop the nearly 14,000-foot peak of Hawaii’s Mauna Kea, an inactive volcano. The altitude puts them above 40 percent of Earth’s atmosphere and most of its water vapor, which hinders infrared wavelengths— that astronomers like to study—from passing through. What does which refer to in Paragraph F?