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: 'man sitting on the side of a van playing the guitar'. Find frequency of the letter 'm'

SOLUTION: 1

PROBLEM: Sentence: 'a couple of wooden benches next to a stone wall'. Find frequency of the letter 'c'

SOLUTION:
2