16458
In 1909 , Hans Geiger and Ernest Marsden conducted experiments with thin sheets of gold .
 person: Hans Geiger; person: Ernest Marsden
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: Hans Geiger, Ernest Marsden 
Answer:
 person: Hans Geiger; person: Ernest Marsden