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: 'this is a close up view of a tennis player during the game'. Find frequency of the letter 't'

Answer: 3


Question: Sentence: 'a white bathroom sink sitting next to a toilet'. Find frequency of the letter 'i'

Answer: 5


Question: Sentence: 'a clown, teddy bear and troll doll for sale in a store'. Find frequency of the letter 'n'

Answer:
3