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 piece of meat covered in ketchup next to a hamburger on a green plate'. Find frequency of the letter 'g'

Answer: 2


Question: Sentence: 'a person on a sidewalk jumping with an umbrella'. Find frequency of the letter 'a'

Answer: 5


Question: Sentence: 'a man riding a white surfboard on top of a wave'. Find frequency of the letter 'n'

Answer:
3