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: 'man riding a skate board down the little board way'. Find frequency of the letter 'k'

Answer: 1


Question: Sentence: 'a red fire hydrant opened and spilling water'. Find frequency of the letter 'd'

Answer: 4


Question: Sentence: 'a zebra on the road walking pass a car'. Find frequency of the letter 'p'

Answer:
1