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

Sentence: 'a boy swinging a bat while playing baseball'. Find frequency of the letter 'h'
1

Sentence: 'a person standing operating a cell phone in a room'. Find frequency of the letter 'n'
6

Sentence: 'a large dog sitting next to a boy near a bench'. Find frequency of the letter 'g'

3