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 two computers on a table'. Find frequency of the letter 'r'

Answer: 2

Question: Sentence: 'two women standing next to each other holding tennis rackets'. Find frequency of the letter 't'

Answer: 7

Question: Sentence: 'an abandoned car and a cow on a field'. Find frequency of the letter 'c'

Answer:
2