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

[EX Q]: Sentence: 'a knife a cutting board some bananas and a toaster'. Find frequency of the letter 'i'
[EX A]: 2

[EX Q]: Sentence: 'a cat that is standing next to an open suitcase'. Find frequency of the letter 'e'
[EX A]: 3

[EX Q]: Sentence: 'a man is standing in front of the entrance to maxwell street depot'. Find frequency of the letter 'i'
[EX A]:
3