TASK DEFINITION: In this task, you need to count the number of times the given letter appears in the given sentence.
PROBLEM: Sentence: 'a person riding a skate board on a city street'. Find frequency of the letter 'a'

SOLUTION: 5

PROBLEM: Sentence: 'the skateboarder is jumping over a huge statue of a shoe'. Find frequency of the letter 'i'

SOLUTION: 2

PROBLEM: Sentence: 'man wearing a hat and scarf carrying a striped box'. Find frequency of the letter 'a'

SOLUTION:
8