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

[EX Q]: Sentence: 'there are two men sitting on a couch playing video games'. Find frequency of the letter 'v'
[EX A]: 1

[EX Q]: Sentence: 'a woman walking with a child that is in a wheelchair'. Find frequency of the letter 'k'
[EX A]: 1

[EX Q]: Sentence: 'a close-up of a man wearing a tie and glasses'. Find frequency of the letter 'n'
[EX A]:
3