instruction:
In this task, you need to count the number of times the given letter appears in the given sentence.
question:
Sentence: 'there is a zebra that is walking enar a car'. Find frequency of the letter 'r'
answer:
4


question:
Sentence: 'a stop sign next to houses with christmas lights'. Find frequency of the letter 's'
answer:
7


question:
Sentence: 'a young man is sitting down with his skateboard'. Find frequency of the letter 'n'
answer:

4