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

[Q]: Sentence: 'a jet flying through the clear blue sky'. Find frequency of the letter 'g'
[A]: 2


[Q]: Sentence: 'two people are riding on canoes down a river'. Find frequency of the letter 'e'
[A]: 5


[Q]: Sentence: 'a trio of older looking suitcases in multiple colors'. Find frequency of the letter 'i'
[A]:
5