instruction:
In this task, you need to count the number of times the given letter appears in the given sentence.
question:
Sentence: 'a group of workers washing and cleaning fruits and vegetables'. Find frequency of the letter 'i'
answer:
3


question:
Sentence: 'a boy catching a frisbee while standing ins bunch of leaves'. Find frequency of the letter 'a'
answer:
5


question:
Sentence: 'three men stand in front of the small airplane'. Find frequency of the letter 'o'
answer:

2