instruction:
In this task, you need to count the number of times the given letter appears in the given sentence.
question:
Sentence: 'a airplane view of a big factory some people and cars'. Find frequency of the letter 'f'
answer:
2


question:
Sentence: 'a cat that is standing next to an open suitcase'. Find frequency of the letter 'e'
answer:
3


question:
Sentence: 'a skate boarder doing a trick in an indoor space'. Find frequency of the letter 'n'
answer:

4