Assertion: eye chart's letter | /r/CapableOf | subtend an angle of 5of arc
Facets:
value: at that distance
type: LOCATION
value: at the person’s eye
type: LOCATION
Source sentences:
text: A person with 20/20 vision could stand 30 feet away from a test chart and just decipher a 20/30 letter on the chart, since at that distance a 20/30 letter would subtend an angle of 5' of arc at the person’s eye.