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

[Q]: Sentence: 'a white bowl filled with peeled orange slices'. Find frequency of the letter 's'
[A]: 2


[Q]: Sentence: 'flower in a vase full of water sitting on a stand '. Find frequency of the letter 'l'
[A]: 3


[Q]: Sentence: 'a snowboarder going over a jump on a pink board'. Find frequency of the letter 'o'
[A]:
6