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 small boy in a high chair eating a cupcake'. Find frequency of the letter 'i'

Answer: 4


Question: Sentence: 'a group of people seated in chairs together and facing the same direction, with one man holding a soccer ball in his hands'. Find frequency of the letter 'm'

Answer: 2


Question: Sentence: 'three dogs are sitting looking outside of a window'. Find frequency of the letter 'i'

Answer:
5