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: 'a piece of meat covered in ketchup next to a hamburger on a green plate'. Find frequency of the letter 'g'
[EX A]: 2

[EX Q]: Sentence: 'two red buses parked in a stationary position'. Find frequency of the letter 'r'
[EX A]:
3