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: 'this is a sign in front of a large cathedral'. Find frequency of the letter 'a'

Answer: 5


Question: Sentence: 'two computers and a laptop set up on a desk'. Find frequency of the letter 'r'

Answer: 1


Question: Sentence: 'there are many people enjoying the day at the beach'. Find frequency of the letter 't'

Answer:
4