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: 'there is a zebra that is walking enar a car'. Find frequency of the letter 'r'

Answer: 4


Question: Sentence: 'a giraffe sticking it's tongue out near a window'. Find frequency of the letter 'a'

Answer: 4


Question: Sentence: 'a woman on a court swinging a tennis racket'. Find frequency of the letter 's'

Answer:
2