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

Sentence: 'a white bowl filled with peeled orange slices'. Find frequency of the letter 's'
2

Sentence: 'three young people goofing around; one of the guys has a football, the girl has a teddy bear'. Find frequency of the letter 'd'
3

Sentence: 'a surfer rides his board on the crest of a wave'. Find frequency of the letter 'e'

5