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: 'a man playing baseball on a television set'. Find frequency of the letter 'l'

Answer: 4


Question: Sentence: 'there is a woman skateboarding and a man next to her'. Find frequency of the letter 'a'

Answer:
7