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 glass bowl of raw broccoli, a ceramic bowl of raw green chili peppers, and steel bowl of raw daikon'. Find frequency of the letter 'a'

Answer: 9

Question: Sentence: 'a picture of two men on a motorcycle in front of a railroad track'. Find frequency of the letter 'n'

Answer: 4

Question: Sentence: 'a one armed woman surfing in the ocean'. Find frequency of the letter 'i'

Answer:
2