In this task, you need to count the number of times the given letter appears in the given sentence.
--------
Question: Sentence: 'this is an image of a woman playing tennis'. Find frequency of the letter 'f'

Answer: 1


Question: Sentence: 'a group of cows that are standing in the grass'. Find frequency of the letter 'g'

Answer: 3


Question: Sentence: 'a white toilet and a dark cherry paneled wall'. Find frequency of the letter 'r'

Answer:
3