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: 'a man paddle boarding by a boat dock in a city'. Find frequency of the letter 'o'

Answer: 3


Question: Sentence: 'two people are skiing down a snow covered hill'. Find frequency of the letter 'o'

Answer:
5