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

[EX Q]: Sentence: 'a social occasion of people are uncovered before the open day'. Find frequency of the letter 'c'
[EX A]: 4

[EX Q]: Sentence: 'a couple of men standing inside of a liquor store'. Find frequency of the letter 'p'
[EX A]: 1

[EX Q]: Sentence: 'three bananas are lined up next to the computer'. Find frequency of the letter 'e'
[EX A]:
7