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

[EX Q]: Sentence: 'two people holding their skies in a snowy resort'. Find frequency of the letter 'n'
[EX A]: 3

[EX Q]: Sentence: 'two giraffes, one standing and one laying down'. Find frequency of the letter 'g'
[EX A]: 3

[EX Q]: Sentence: 'train on tracks with water tower for davis junction in the rear'. Find frequency of the letter 'a'
[EX A]:
5