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

Sentence: 'a man is taking a picture of a man and woman'. Find frequency of the letter 'a'
8

Sentence: 'a plastic tray that has different foods inside of it'. Find frequency of the letter 't'
6

Sentence: 'man riding a surfboard under a large wave'. Find frequency of the letter 'i'

2