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

[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: 'a couple of boys in a field playing baseball'. Find frequency of the letter 'i'
[EX A]: 3

[EX Q]: Sentence: 'a group of people posing on motorcycles for a photo'. Find frequency of the letter 'n'
[EX A]:
2