instruction:
In this task, you need to count the number of times the given letter appears in the given sentence.
question:
Sentence: 'a picture of two computers on a table'. Find frequency of the letter 'r'
answer:
2


question:
Sentence: 'a large grass pasture land with sheep grazing on grass'. Find frequency of the letter 'a'
answer:
7


question:
Sentence: 'a bunch of soft pretzels are waiting to be sold'. Find frequency of the letter 'p'
answer:

1