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 line of people on motorcycles on the road'. Find frequency of the letter 'e'

Answer: 5


Question: Sentence: 'a couple of buses parked on the side of the street'. Find frequency of the letter 'b'

Answer: 1


Question: Sentence: 'a man doing a trick on his skateboard at a skate park'. Find frequency of the letter 't'

Answer:
4