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

Sentence: 'there is a woman pointing at something with her dog'. Find frequency of the letter 'i'
5

Sentence: 'a man on a skateboard going down a ramp while people are watching'. Find frequency of the letter 'w'
3

Sentence: 'a garden is in the process of growing outside a fenced area'. Find frequency of the letter 'a'

5