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

[EX Q]: Sentence: 'a small white plane sitting on top of the ocean'. Find frequency of the letter 'e'
[EX A]: 4

[EX Q]: Sentence: 'a tv in a glass mirror in the bathroom'. Find frequency of the letter 'h'
[EX A]: 2

[EX Q]: Sentence: 'a herd of giraffes in tall african grass'. Find frequency of the letter 'a'
[EX A]:
6

