TASK DEFINITION: In this task, you need to count the number of times the given letter appears in the given sentence.
PROBLEM: Sentence: 'a white toilet sitting next to a toilet paper roller'. Find frequency of the letter 'o'

SOLUTION: 4

PROBLEM: Sentence: 'a man holding a frisbee high into the air'. Find frequency of the letter 'a'

SOLUTION: 4

PROBLEM: Sentence: 'a baby with hands in the air as her birthday cake comes out'. Find frequency of the letter 'r'

SOLUTION:
3