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

[EX Q]: Sentence: 'a woman in a messy kitchen with a child'. Find frequency of the letter 'a'
[EX A]: 4

[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 talbe with plates of food and a mason jar'. Find frequency of the letter 'i'
[EX A]:
1