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: 'three young children playing with a ball in front of a huge bridge'. Find frequency of the letter 'e'

Answer: 5


Question: Sentence: 'a surfer wipes out on a huge wave'. Find frequency of the letter 'a'

Answer: 3


Question: Sentence: 'many people in a crowd and one is holding up a cellphone'. Find frequency of the letter 'y'

Answer:
1