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

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

[EX Q]: Sentence: 'small black bird with red on its head standing on a tree branch'. Find frequency of the letter 'b'
[EX A]: 3

[EX Q]: Sentence: 'a small silver basket with bananas and a sign'. Find frequency of the letter 'i'
[EX A]:
3