Assertion: railroad's track | /r/HasProperty | laid on a level grade
Facets:
Source sentences:
text: The railroad companies were paid $16,000 per mile (approximately $455,000 per mile today) for track laid on a level grade, $32,000 per mile (about $911,000 per mile today) for track laid in foothills, and $48,000 per mile (or about $1,366,000 per mile today) for track laid in mountains.