question: What sentence would provide a factual answer to this question: "The looseness of soil increases the amount of what in it?"

answer: the looseness of soil increases the amount of oxygen in that soil

question: What sentence would provide a factual answer to this question: "it's important to recycle metals because they are"

answer: metal is a nonrenewable resource

question: What sentence would provide a factual answer to this question: "a student leaves a nail line on a mineral sample, so that mineral can be described as what?"

answer:
if a mineral can be scratched by a fingernail then that mineral is soft