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

Sentence: 'a teenager witting on a futon couch holding gaming controls in both hands'. Find frequency of the letter 'c'
3

Sentence: 'food sitting in bowls on table with checked tablecloth'. Find frequency of the letter 't'
6

Sentence: 'a black bear walking over very rocky terrain'. Find frequency of the letter 'e'

4