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

[Q]: Sentence: 'a toilet sits in a cluttered bathroom next to a sink'. Find frequency of the letter 'a'
[A]: 4

[Q]: Sentence: 'a large cooked pizza on a dining table'. Find frequency of the letter 'n'
[A]: 3

[Q]: Sentence: 'a clean and tidy kitchen with modern decor'. Find frequency of the letter 'a'
[A]:
3