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

[Q]: Sentence: 'a person trying to flip a skateboard in a garage'. Find frequency of the letter 'a'
[A]: 7


[Q]: Sentence: 'apples, pears, and oranges are piled up for sale'. Find frequency of the letter 'a'
[A]: 6


[Q]: Sentence: 'a little child on little bitty skis in the snow'. Find frequency of the letter 'i'
[A]:
6