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

[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: 'hotel towels with sunglasses perched and hotel business cards and catalog'. Find frequency of the letter 'o'
[EX A]: 4

[EX Q]: Sentence: 'people and a dog walking down a highway in a marathon'. Find frequency of the letter 'w'
[EX A]:
3