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

[EX Q]: Sentence: 'soccer players on opposite teams fight for control over a ball'. Find frequency of the letter 't'
[EX A]: 4

[EX Q]: Sentence: 'a man sitting in front of a laptop computer next to a child'. Find frequency of the letter 'e'
[EX A]: 2

[EX Q]: Sentence: 'a skier zooms down a hillside under a clear blue sky'. Find frequency of the letter 'e'
[EX A]:
5