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 gray elephant is in a grassy field'. Find frequency of the letter 'e'

Answer: 3


Question: Sentence: 'one man grabbing another at a table while laughing'. Find frequency of the letter 'n'

Answer: 5


Question: Sentence: 'a family of three plays a video game together'. Find frequency of the letter 'm'

Answer:
2