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: 'some cubbies with towels in a blue bathroom'. Find frequency of the letter 'l'

Answer: 2


Question: Sentence: 'a person on a surfboard in the surf of a wave'. Find frequency of the letter 's'

Answer: 3


Question: Sentence: 'two zebra standing next to each other on a dirt field'. Find frequency of the letter 'a'

Answer:
4