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: 'two men in black wet suits beside a white surfboard'. Find frequency of the letter 'e'

Answer: 5


Question: Sentence: 'a snow filled mountain with a guy with ski's'. Find frequency of the letter 'f'

Answer: 1


Question: Sentence: 'a man riding a skateboard on a metal platform'. Find frequency of the letter 'a'

Answer:
8