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

Sentence: 'a group of people are playing soccer on a beach'. Find frequency of the letter 'l'
2

Sentence: 'three people are gathered around sitting on a park bench'. Find frequency of the letter 'g'
2

Sentence: 'a meter is iced over and in between shows a woman walking'. Find frequency of the letter 'e'

7