instruction:
Given a fact, create a question that can be answered using the fact. Construct the question such that it is unambiguous, has a unique answer and the answer can be given using the fact.
question:
Fact: a seismograph is a kind of tool for measuring the size of an earthquake
answer:
a seismograph is a kind of tool for measuring the size of?


question:
Fact: a cactus stem is used for storing water
answer:
Someone stranded in the Sahara can potentially save their life with a?


question:
Fact: as the roughness of something increases , the friction of that something will increase when its surface moves against another surface
answer:

If I run my finger across a sheet of plain paper and a sheet of sand paper, which will have greater friction?