instruction:
In this task, you need to count the number of times the given letter appears in the given sentence.
question:
Sentence: 'an commercial airline airplane flies above the clouds'. Find frequency of the letter 'n'
answer:
3


question:
Sentence: 'a person dressed all in black snowboarding down a slope'. Find frequency of the letter 'e'
answer:
4


question:
Sentence: 'this is a beautiful photo of a person standing on the beach near the water'. Find frequency of the letter 'i'
answer:

4