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: 'seagulls sit on the posts of a seaside balcony by a clock tower'. Find frequency of the letter 'g'

Answer: 1

Question: Sentence: 'a tennis player that is running to get the tennis ball'. Find frequency of the letter 't'

Answer: 7

Question: Sentence: 'a set of three computer monitors sitting on top of a desk'. Find frequency of the letter 'e'

Answer:
5