question: What sentence would provide a factual answer to this question: "Changes to the earth can be done as a result of"

answer: natural events usually cause changes to Earth 's surface

question: What sentence would provide a factual answer to this question: "A source of heat is used to make"

answer: an oven is a source of heat

question: What sentence would provide a factual answer to this question: "If an instrument is played, this may occur"

answer:
An example of playing a musical instrument is hitting the keys of a piano