Given a scientific passage and an answer, generate a question for the given answer.

Input: Consider Input: Passage: Christopher Auyeung, using bat image by User:Rugby471/Wikimedia Commons. Bats use echolocation to identify the location of objects . CC BY-NC 3.0 (bat image available under public domain). Answer: echolocation

Output: What do bats use to determine the location of objects?

Input: Consider Input: Passage: Graphs are very useful tools in science because they display data visually. Three commonly used types of graphs are bar graphs, circle graphs, and line graphs. Each type of graph is suitable for a different type of data. Answer: graphs

Output: Bar, circle, and line are examples of what kind of data visualization?

Input: Consider Input: Passage: Ice, water, and steam appear quite differently to the eye. If you were to look at these three states of matter on the molecular level, you would see that the arrangement of molecules is very different here as well. However, solids and liquids have definite volumes, unlike gases which tend to take on the shape of their container. In this lesson, you will learn about the unique behavior of gas particles on a molecular level and the basis for kinetic molecular theory. Answer: solids and liquids
Output: Which two states of matter have definite volumes?