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

[Q]: Sentence: 'a dog has found a rather large stick for playing fetch'. Find frequency of the letter 't'
[A]: 3


[Q]: Sentence: 'a scene at night; a plane alone on a runway with lit-up city buildings on the horizon'. Find frequency of the letter 'w'
[A]: 2


[Q]: Sentence: 'a close of a persons foot standing behind a group of guys with surfboards'. Find frequency of the letter 'f'
[A]:
4