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 woman in a messy kitchen with a child'. Find frequency of the letter 'a'

Answer: 4

Question: Sentence: 'a man riding on the back of a white horse next to other horses'. Find frequency of the letter 'o'

Answer: 6

Question: Sentence: 'someone is doing something that is extremely fun'. Find frequency of the letter 'g'

Answer:
2