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

[Q]: Sentence: 'a bunch of broken down trains sit in a yard'. Find frequency of the letter 'n'
[A]: 5


[Q]: Sentence: 'two men are playing a video game as another sits watching'. Find frequency of the letter 'a'
[A]: 7


[Q]: Sentence: 'planes and baggage cars at a busy airport'. Find frequency of the letter 'g'
[A]:
3