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

[EX Q]: Sentence: 'a room with a big screen television and a couch'. Find frequency of the letter 'h'
[EX A]: 2

[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 boy wearing a red and blue ski outfit gets ready to hit the slopes'. Find frequency of the letter 's'
[EX A]:
4