TASK DEFINITION: In this task, you need to count the number of times the given letter appears in the given sentence.
PROBLEM: Sentence: 'two men are playing a video game as another sits watching'. Find frequency of the letter 'a'

SOLUTION: 7

PROBLEM: Sentence: 'a bunch of people are standing out in a field a red one has their arms out as a white ball is in the air'. Find frequency of the letter 'e'

SOLUTION: 9

PROBLEM: Sentence: 'three teenagers are practicing playing soccer in the park'. Find frequency of the letter 'c'

SOLUTION:
4