instruction:
In this task, you need to count the number of times the given letter appears in the given sentence.
question:
Sentence: 'small airplane in the process of taking off'. Find frequency of the letter 'e'
answer:
3


question:
Sentence: 'an image of a cautionary construction sign'. Find frequency of the letter 'a'
answer:
5


question:
Sentence: 'a close up of pizza on a wooden table with people in the background'. Find frequency of the letter 'n'
answer:

4