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 surfer is in the middle of an ocean wave'. Find frequency of the letter 'i'

Answer: 3


Question: Sentence: 'oranges are sitting in a bowl on a table'. Find frequency of the letter 'a'

Answer: 5


Question: Sentence: 'a woman sitting in a  chair while playing an instrument'. Find frequency of the letter 'o'

Answer:
1