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: 'pedestrian in stripe clothing standing on street corner'. Find frequency of the letter 's'

Answer: 4


Question: Sentence: 'man in air skateboarding on street with building'. Find frequency of the letter 't'

Answer: 4


Question: Sentence: 'a woman in a red top holding something with a white and red background'. Find frequency of the letter 'a'

Answer:
6