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 picture of a machine built next to a street'. Find frequency of the letter 'x'

Answer: 1


Question: Sentence: 'a bird is standing on the ledge of the building'. Find frequency of the letter 't'

Answer: 3


Question: Sentence: 'a vegetable stand with various types of vegetables'. Find frequency of the letter 'g'

Answer:
2