TASK DEFINITION: In this task, you need to count the number of times the given letter appears in the given sentence.
PROBLEM: Sentence: 'a blue fire hydrant painted on the bottom of it'. Find frequency of the letter 'h'

SOLUTION: 2

PROBLEM: Sentence: 'the counter of a doctor's office, including a laptop, cotton swabs, and tongue depressors'. Find frequency of the letter 'g'

SOLUTION: 2

PROBLEM: Sentence: 'a train is approaching on a railroad track'. Find frequency of the letter 'c'

SOLUTION:
2