instruction:
In this task, you need to count the number of times the given letter appears in the given sentence.
question:
Sentence: 'an old woman is holding her cat in front of a camera'. Find frequency of the letter 'r'
answer:
3


question:
Sentence: 'a man flying through the air on a bicycle'. Find frequency of the letter 'u'
answer:
1


question:
Sentence: 'a picture with a dove cut out as a person holds scissors'. Find frequency of the letter 'i'
answer:

3