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 large group of motorcycles parked along a street'. Find frequency of the letter 'a'

Answer: 5


Question: Sentence: 'many different species of sheep in display at a museum'. Find frequency of the letter 'h'

Answer: 1


Question: Sentence: 'a crowd of people walking along a river next to street lights'. Find frequency of the letter 'e'

Answer:
6