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

Sentence: 'a closet with a fan, luggage and various boxes'. Find frequency of the letter 'a'
6

Sentence: 'a doll with huge eyes and black hair with blunt bangs holds a red umbrella'. Find frequency of the letter 'e'
5

Sentence: 'small boxer dog on cement and stone steps'. Find frequency of the letter 'x'

1