instruction:
In this task, you need to count the number of times the given letter appears in the given sentence.
question:
Sentence: 'young girl playing with refrigerator magnet while kneeling on floor'. Find frequency of the letter 'n'
answer:
6

question:
Sentence: 'a group of people stand inside of a big room'. Find frequency of the letter 'o'
answer:
6

question:
Sentence: 'a large jetliner landing on top of a runway'. Find frequency of the letter 'r'
answer:
3