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

[EX Q]: Sentence: 'older man getting ready to swing his bat at a ball on a stand in front of a group of viewers'. Find frequency of the letter 'n'
[EX A]: 7

[EX Q]: Sentence: 'a group of people seated in chairs together and facing the same direction, with one man holding a soccer ball in his hands'. Find frequency of the letter 'm'
[EX A]: 2

[EX Q]: Sentence: 'a bathroom stale with a toilet and an animal drinking water inside'. Find frequency of the letter 'o'
[EX A]:
3