instruction:
In this task, you need to count the number of times the given letter appears in the given sentence.
question:
Sentence: 'a woman is taking a sip of a drink from a glass'. Find frequency of the letter 'i'
answer:
4


question:
Sentence: 'a woman throwing a frisbee on a field'. Find frequency of the letter 's'
answer:
1


question:
Sentence: 'a man is getting ready to take a swing at a baseball'. Find frequency of the letter 'a'
answer:

9