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

[EX Q]: Sentence: 'a white toilet sitting next to a toilet paper roller'. Find frequency of the letter 'o'
[EX A]: 4

[EX Q]: Sentence: 'a young boy bouncing a tennis ball on a tennis racquet'. Find frequency of the letter 'a'
[EX A]: 5

[EX Q]: Sentence: 'a man riding a surfboard on top of a wave'. Find frequency of the letter 'w'
[EX A]:
1