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 man sitting inside a green military truck talking to someone'. Find frequency of the letter 'i'

Answer: 7


Question: Sentence: 'a passenger train that is going over a bridge'. Find frequency of the letter 't'

Answer: 3


Question: Sentence: 'a wildebeest walking with a giraffe in the distance'. Find frequency of the letter 'k'

Answer:
1