instruction:
In this task, you need to count the number of times the given letter appears in the given sentence.
question:
Sentence: 'two people under an umbrella while walking down a sidewalk'. Find frequency of the letter 'i'
answer:
3


question:
Sentence: 'a crowd of people skiing and enjoying the snow'. Find frequency of the letter 'o'
answer:
5


question:
Sentence: 'an elephant in dirt area standing over a fence'. Find frequency of the letter 'a'
answer:

6