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

[EX Q]: Sentence: 'a kitchen with hanging lights, an island with sink and bar stools, a refrigerator, small pantry door, wooden cabinets and shiny wood floor'. Find frequency of the letter 'n'
[EX A]: 12

[EX Q]: Sentence: 'a police officer who is riding on a horse'. Find frequency of the letter 'p'
[EX A]: 1

[EX Q]: Sentence: 'a picture of a small country store with a truck and car parked outside'. Find frequency of the letter 'u'
[EX A]:
4