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 double decker bus with a lot of people on board'. Find frequency of the letter 'l'

Answer: 3


Question: Sentence: 'the meal is served and ready to be eaten'. Find frequency of the letter 'e'

Answer: 8


Question: Sentence: 'a couple of men with surfboards at the beach'. Find frequency of the letter 'h'

Answer:
3