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 man in a suit makes the first slice into a cake'. Find frequency of the letter 't'

Answer: 4


Question: Sentence: 'a black computer with a screen reading "press any key to begin."'. Find frequency of the letter 'a'

Answer: 5


Question: Sentence: 'a dog is sleeping in a bed underneath a desk'. Find frequency of the letter 'd'

Answer:
4