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 red building with a crowd of people outside it near the water'. Find frequency of the letter 'e'

Answer: 7


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: 'the two trains are inside of the station'. Find frequency of the letter 't'

Answer:
6