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

[EX Q]: Sentence: 'a young boy standing in front of a counter with dougnuts'. Find frequency of the letter 'o'
[EX A]: 6

[EX Q]: Sentence: 'a street scene looking at the back of the stop sign'. Find frequency of the letter 't'
[EX A]: 6

[EX Q]: Sentence: 'a bowl of rice with chicken and broccoli'. Find frequency of the letter 'n'
[EX A]:
2