TASK DEFINITION: In this task, you need to count the number of times the given letter appears in the given sentence.
PROBLEM: Sentence: 'the snowboarder wearing a dark helmet sprays snow into the air'. Find frequency of the letter 'w'

SOLUTION: 3

PROBLEM: Sentence: 'a woman in a messy kitchen with a child'. Find frequency of the letter 'a'

SOLUTION: 4

PROBLEM: Sentence: 'two people dressed in black on a blue motorcycle'. Find frequency of the letter 'e'

SOLUTION:
6