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

[Q]: Passage: A snowflake is made of ice, or water in the solid state. A solid is one of four well-known states of matter. The other three states are liquid, gas, and plasma. Compared with these other states of matter, solids have particles that are much more tightly packed together. The particles are held rigidly in place by all the other particles around them so they can't slip past one another or move apart. This gives solids a fixed shape and a fixed volume. Answer: plasma
[A]: What state of matter completes the list: solid, liquid, gas?

[Q]: Passage: Figure 6.11 The frictional force supplies the centripetal force and is numerically equal to it. Centripetal force is perpendicular to velocity and causes uniform circular motion. The larger the F c , the smaller the radius of curvature r and the sharper the curve. The second curve has the same v , but a larger. Answer: centripetal force
[A]: What force is perpendicular to velocity and causes uniform circular motion?

[Q]: Passage: Transcription takes place in three steps: initiation, elongation, and termination. The steps are illustrated in Figure below . Answer: transcription
[A]:
Initiation, elongation, and termination are the three steps of what?