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 burning wood stove has a tea pot sitting on top of it and is full of wood'. Find frequency of the letter 'a'

Answer: 5


Question: Sentence: 'two little girls playing with a bat and a tennis ball'. Find frequency of the letter 'w'

Answer: 2


Question: Sentence: 'a batter and umpire and a catcher playing baseball'. Find frequency of the letter 'e'

Answer:
4