instruction:
In this task, you need to count the number of times the given letter appears in the given sentence.
question:
Sentence: 'a black bear sitting in the grass taking a rest'. Find frequency of the letter 'a'
answer:
6


question:
Sentence: 'one man grabbing another at a table while laughing'. Find frequency of the letter 'n'
answer:
5


question:
Sentence: 'a person on a baseball field swinging a bat'. Find frequency of the letter 's'
answer:

3