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

Sentence: 'a street at night with trees and streetlights on'. Find frequency of the letter 't'
9

Sentence: 'a woman with short, brown hair is looking into a circular mirror and holding a camera up to her cheek'. Find frequency of the letter 'e'
4

Sentence: 'a bird outside standing on a table looking up'. Find frequency of the letter 'b'

2