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 microwave oven with a yellow note on the door'. Find frequency of the letter 'w'

Answer: 3


Question: Sentence: 'a tennis player that is running to get the tennis ball'. Find frequency of the letter 't'

Answer: 7


Question: Sentence: 'bench sitting on sand surrounded by colorful flowers'. Find frequency of the letter 'b'

Answer:
2