In this task, you need to count the number of times the given letter appears in the given sentence.
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Question: Sentence: 'two people are riding on canoes down a river'. Find frequency of the letter 'e'

Answer: 5


Question: Sentence: 'a black horse with a white dot on its forehead'. Find frequency of the letter 't'

Answer: 4


Question: Sentence: 'a kitchen table with chairs and a space heater'. Find frequency of the letter 'b'

Answer:
1