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 toilet filled with a brown liner and dirty water'. Find frequency of the letter 't'

Answer: 5

Question: Sentence: 'a toasted sub sandwich is next to a salad'. Find frequency of the letter 'a'

Answer: 6

Question: Sentence: 'a round white plate on a table that has french fries, coleslaw and a sandwich cut in half'. Find frequency of the letter 'a'

Answer:
11