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

[Q]: Sentence: 'a cat sprawls out and sleeps on its back on a lounge chair with an acorn theme'. Find frequency of the letter 'r'
[A]: 3


[Q]: Sentence: 'a group of workers washing and cleaning fruits and vegetables'. Find frequency of the letter 'i'
[A]: 3


[Q]: Sentence: 'three men in military suits are sitting on a bench,'. Find frequency of the letter 'a'
[A]:
3