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

Sentence: 'the bathroom is in need of remodel'. Find frequency of the letter 'e'
5

Sentence: 'several zebras  and a giraffe in an enclosure'. Find frequency of the letter 's'
3

Sentence: 'several double decker buses driving down a popular strip'. Find frequency of the letter 'u'

3