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 swinging a tennis racquet towards a tennis ball'. Find frequency of the letter 'e'

Answer: 3


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

Answer: 7


Question: Sentence: 'there are many objects sitting on the table'. Find frequency of the letter 'n'

Answer:
3