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

[EX Q]: Sentence: 'a small dog sits in the rear window of a car'. Find frequency of the letter 'm'
[EX A]: 1

[EX Q]: Sentence: 'a bus is stopped in front of a graphic statue'. Find frequency of the letter 'e'
[EX A]: 2

[EX Q]: Sentence: 'a colorful umbrella stands apart from a black and white photo of people standing in front of a statue'. Find frequency of the letter 'n'
[EX A]:
6