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

[EX Q]: Sentence: 'town clocks affixed to a tall, brick building'. Find frequency of the letter 'r'
[EX A]: 1

[EX Q]: Sentence: 'a closet with a fan, luggage and various boxes'. Find frequency of the letter 'a'
[EX A]: 6

[EX Q]: Sentence: 'a young female wearing shorts on a skateboard'. Find frequency of the letter 's'
[EX A]:
3