7817
The earliest reasonably accurate estimate of the speed of sound in air was made by William Derham and acknowledged by Isaac Newton .
 person: William Derham; person: Isaac Newton
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: William Derham, Isaac Newton 
Answer:
 person: William Derham; person: Isaac Newton