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

[EX Q]: Sentence: 'some food on plates next to each other on a table'. Find frequency of the letter 'e'
[EX A]: 6

[EX Q]: Sentence: 'a bed with a dog laying on it next to two laptop computers'. Find frequency of the letter 'n'
[EX A]: 3

[EX Q]: Sentence: 'a young man holding a nintendo wii controller'. Find frequency of the letter 'd'
[EX A]:
2