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 small white plane sitting on top of the ocean'. Find frequency of the letter 'e'
[EX A]: 4

[EX Q]: Sentence: 'some cupcakes with different colors on cooling racks'. Find frequency of the letter 'r'
[EX A]:
3