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

[EX Q]: Sentence: 'a woman fully dressed as a geisha'. Find frequency of the letter 'm'
[EX A]: 1

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

[EX Q]: Sentence: 'a man plays baseball with a young person'. Find frequency of the letter 'r'
[EX A]:
1