instruction:
In this task, you need to count the number of times the given letter appears in the given sentence.
question:
Sentence: 'men standing in the grass with a frisbee'. Find frequency of the letter 'a'
answer:
3


question:
Sentence: 'the little girl is flying her kite in the field'. Find frequency of the letter 'i'
answer:
7


question:
Sentence: 'a fruit stand has various fruits on the table'. Find frequency of the letter 's'
answer:

4