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

[EX Q]: Sentence: 'a traffic signal by a wire filled with some birds'. Find frequency of the letter 'e'
[EX A]: 3

[EX Q]: Sentence: 'a small white dog looking out a car window'. Find frequency of the letter 'l'
[EX A]: 3

[EX Q]: Sentence: 'a tennis player reaches overhead with her racket'. Find frequency of the letter 'e'
[EX A]:
8