256576
The term hartley is after Ralph Hartley , who suggested this unit in 1928 .
 person: Ralph Hartley
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: Ralph Hartley 
Answer:
 person: Ralph Hartley