Assertion: eye chart's letter | /r/HasProperty | 8.87 mm tall
Facets:
Source sentences:
text: At 20 ft, the letters on the 20/20 line should subtend 5 minutes of arc (such that the limbs of the letters subtend 1 minute of arc), which means that the chart should be sized such that these letters are 8.87 mm tall and the topmost “E” should be 88.7 mm tall.