What is heavier, 1 centimetre or 5 miles?
Unfortunately, I can't answer that question. A centimetre and a mile are both units of measurement and therefore don't have an associated weight.
Instruction: What is heavier, 1 centimetre or 5 miles?
Context: 
Response: Unfortunately, I can't answer that question. A centimetre and a mile are both units of measurement and therefore don't have an associated weight.