You are presented with the quiz "What causes day and night?"   But you don't know the answer, so you turn to your teacher to ask for hints. He says that "aplanet rotating causes cycles of day and night on that planet" and "the gravitational pull of the major planets alters the orbital period from revolution to revolution".   So, what's the best answer to the question?

Answer: Revolution around the sun


You are presented with the quiz "How is sandstone formed?"   But you don't know the answer, so you turn to your teacher to ask for hints. He says that "sedimentary rocks are formed by deposition" and "sedimentary Rocks One of the commonest sedimentary rocks is sandstone".   So, what's the best answer to the question?

Answer: Deposition


You are presented with the quiz "What helps movement?"   But you don't know the answer, so you turn to your teacher to ask for hints. He says that "flagella help prokaryotes move" and "flagella and cilia are similar in structure".   So, what's the best answer to the question?

Answer: cilia


You are presented with the quiz "Astronauts require _  food for extended flights"   But you don't know the answer, so you turn to your teacher to ask for hints. He says that "astronauts require preserved food for extended flights" and "mostly for reasons of preservation, some food is dehydrated for consumption here on Earth".   So, what's the best answer to the question?

Answer: