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

[EX Q]: Sentence: 'a tennis player after hitting a shot back to the other side of the court'. Find frequency of the letter 'n'
[EX A]: 3

[EX Q]: Sentence: 'a teenager witting on a futon couch holding gaming controls in both hands'. Find frequency of the letter 'c'
[EX A]: 3

[EX Q]: Sentence: 'the back of a refrigerator in a kitchen'. Find frequency of the letter 'h'
[EX A]:
2