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

[EX Q]: Sentence: 'a close up of a plate with a whole carrot'. Find frequency of the letter 'w'
[EX A]: 2

[EX Q]: Sentence: 'a laptop computer with pictures of giraffes on the homescreen'. Find frequency of the letter 'o'
[EX A]: 5

[EX Q]: Sentence: 'a person on a court with a tennis racket'. Find frequency of the letter 'n'
[EX A]:
4