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

[EX Q]: Sentence: 'a group of men standing around a table cutting a cake'. Find frequency of the letter 'g'
[EX A]: 3

[EX Q]: Sentence: 'a small boy in a high chair eating a cupcake'. Find frequency of the letter 'i'
[EX A]: 4

[EX Q]: Sentence: 'young boy and girl are playing, and the girl holding a white device with a cord'. Find frequency of the letter 'n'
[EX A]:
5