instruction:
In this task, you need to count the number of times the given letter appears in the given sentence.
question:
Sentence: 'a large grass pasture land with sheep grazing on grass'. Find frequency of the letter 'a'
answer:
7


question:
Sentence: 'a tennis player after hitting a shot back to the other side of the court'. Find frequency of the letter 'n'
answer:
3


question:
Sentence: 'a fry pan with a mixture of vegetables in it'. Find frequency of the letter 'e'
answer:

4