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 bird in a tree looking up at branches'. Find frequency of the letter 'e'

Answer: 3


Question: Sentence: 'several zebras  and a giraffe in an enclosure'. Find frequency of the letter 's'

Answer: 3


Question: Sentence: 'man with beanie jumping skateboard off cement ramp'. Find frequency of the letter 'a'

Answer:
5


