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

[Q]: Sentence: 'a dilapidated bench in a park under a tree'. Find frequency of the letter 'p'
[A]: 2


[Q]: Sentence: 'two boys are doing skateboard jumps in the street'. Find frequency of the letter 's'
[A]: 4


[Q]: Sentence: 'surfboard being displayed in stor window with clothes behind it'. Find frequency of the letter 't'
[A]:
4