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: 'soccer players on opposite teams fight for control over a ball'. Find frequency of the letter 't'

Answer: 4


Question: Sentence: 'an image of a cautionary construction sign'. Find frequency of the letter 'a'

Answer: 5


Question: Sentence: 'a city scene that was seen from the other side of a river'. Find frequency of the letter 'o'

Answer:
3