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 is looking at sheep off in a field'. Find frequency of the letter 'm'

Answer: 1


Question: Sentence: 'two computers and a laptop set up on a desk'. Find frequency of the letter 'r'

Answer: 1


Question: Sentence: 'a person riding a snow board on a snowy surface'. Find frequency of the letter 'a'

Answer:
5