In this task, you need to count the number of times the given letter appears in the given sentence.

[Q]: Sentence: 'a young girl skiing down a snowy mountain'. Find frequency of the letter 'l'
[A]: 1


[Q]: Sentence: 'there is a zebra that is walking enar a car'. Find frequency of the letter 'r'
[A]: 4


[Q]: Sentence: 'a fire hydrant on a city street near a pole'. Find frequency of the letter 'n'
[A]:
3