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

[EX Q]: Sentence: 'a group of people walking down a rain soaked street with umbrellas'. Find frequency of the letter 'w'
[EX A]: 3

[EX Q]: Sentence: 'a couple of items that are on the wall'. Find frequency of the letter 'm'
[EX A]: 1

[EX Q]: Sentence: 'statues of elephants, horses and people sitting next to a road that runs past a building'. Find frequency of the letter 't'
[EX A]:
10