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

[EX Q]: Sentence: 'a double parking meter is decorated with a picture of a girl with wings on her feet'. Find frequency of the letter 'r'
[EX A]: 6

[EX Q]: Sentence: 'a boy catching a frisbee while standing ins bunch of leaves'. Find frequency of the letter 'a'
[EX A]: 5

[EX Q]: Sentence: 'a small dog being carried in a backpack'. Find frequency of the letter 'r'
[EX A]:
2