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

[EX Q]: Sentence: 'people fishing and enlarge mountainlake with trees lining the shoreline'. Find frequency of the letter 't'
[EX A]: 4

[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 curious cat reaching down at an object on a television screen'. Find frequency of the letter 'u'
[EX A]:
2