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 boy that is sitting at a table with pizza'. Find frequency of the letter 's'

Answer: 2


Question: Sentence: 'a couple of items that are on the wall'. Find frequency of the letter 'm'

Answer: 1


Question: Sentence: 'a big travel van parked in a loading lane of a hotel'. Find frequency of the letter 'l'

Answer:
4