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

Answer: 7


Question: Sentence: 'a bathroom with a sink, counter top, and mirror is shown'. Find frequency of the letter 'i'

Answer: 4


Question: Sentence: 'a bench is in an overgrown yard by a hose'. Find frequency of the letter 'n'

Answer:
4