46483
In contrast , Young proceeded to show that " a " medium more easily compressible in one direction than in any direction perpendicular to it , as if it consisted of an infinite number of parallel plates connected by a substance somewhat less elastic " admits spheroidal longitudinal wavefronts , as Huygens supposed .
 person: Young; person: Huygens
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: location, person, organization 
Text: {0} 
 Entities: Young, Huygens 
Answer:
 person: Young; person: Huygens