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

[EX Q]: Sentence: 'two young ladies that are dancing in the room together'. Find frequency of the letter 'a'
[EX A]: 4

[EX Q]: Sentence: 'a close up of a train on a track in the dark'. Find frequency of the letter 'a'
[EX A]: 6

[EX Q]: Sentence: 'a couple of individuals are getting to know how to have fun'. Find frequency of the letter 'u'
[EX A]:
3