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

[EX Q]: Sentence: 'a few giraffes standing in a field looking around'. Find frequency of the letter 'e'
[EX A]: 3

[EX Q]: Sentence: 'a little boy sitting on a bed in a bedroom'. Find frequency of the letter 'e'
[EX A]: 3

[EX Q]: Sentence: 'a desktop computer sitting on top of a desk'. Find frequency of the letter 'o'
[EX A]:
5