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 small boat travels on the water next to the shore'. Find frequency of the letter 'a'

Answer: 5


Question: Sentence: 'small airplane in the process of taking off'. Find frequency of the letter 'e'

Answer: 3


Question: Sentence: 'a large motorcycle that has a man dressed in old clothing next to it'. Find frequency of the letter 'a'

Answer:
6