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: 'a view from a bathroom shows an open door'. Find frequency of the letter 'o'

Answer: 7


Question: Sentence: 'a batter, catcher and umpire waiting for the pitch and a major league baseball game'. Find frequency of the letter 'c'

Answer: 3


Question: Sentence: 'a group of people go horseback riding on a large plain'. Find frequency of the letter 'g'

Answer:
4