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

[EX Q]: Sentence: 'an elephant with broken tusks stands in front of a hill and boulders'. Find frequency of the letter 'n'
[EX A]: 7

[EX Q]: Sentence: 'a giraffe sticking it's tongue out near a window'. Find frequency of the letter 'a'
[EX A]: 4

[EX Q]: Sentence: 'a view of a park and some benches with birds on the ground'. Find frequency of the letter 'w'
[EX A]:
2