Assertion: mound's height | /r/HasProperty | proper
Facets:
Source sentences:
text: If the pitcher's mound is at its proper height, the slope from the edge of the plateau to the edge of the mound should drop one inch for every one foot of measurement.
text: If the pitcher's mound is at its proper height, the slope from the edge of the plateau to the edge of the mound should drop one inch for every one foot of measurement.