instruction:
In this task, you need to count the number of times the given letter appears in the given sentence.
question:
Sentence: 'a couple of buildings that has a bus out front'. Find frequency of the letter 'a'
answer:
4


question:
Sentence: 'a young boy standing in front of a counter with dougnuts'. Find frequency of the letter 'o'
answer:
6


question:
Sentence: 'fishing boats are docked in front of a village'. Find frequency of the letter 'n'
answer:

3