instruction:
Given a scientific passage and an answer, generate a question for the given answer.
question:
Passage: With the naked eye, bacteria just look like a slimy smear on a petri dish. How can we study them in more detail? The invention of the microscope has allowed us to see bacteria, cells, and other things too small to be seen with the naked eye. Answer: slimy smear
answer:
How does the bacteria look when seen with the naked eye?

question:
Passage: Each kind of pigment absorbs specific wavelengths (colors) of light (dashed lines). Sunlight contains many different wavelengths, which you see when they separate into a rainbow. Not all colors of light are used in photosynthesis (solid line). Most plants, algae, and photosynthetic bacteria appear green because they reflect green wavelengths. Their pigments have absorbed the violet-blue and red wavelengths. The amount of photosynthesis depends on the wavelength of light available. Beta-carotene is another type of pigment that absorbs sunlight. Answer: rainbow
answer:
Sunlight contains many different wavelengths, which you see when they separate into what?

question:
Passage: Radio waves are electromagnetic waves with the longest wavelengths, lowest frequencies, and least amount of energy. They are used for radio and television broadcasts and many other purposes. Answer: radio waves
answer:
What waves do radio and television use?