TASK DEFINITION: In this task, you need to count the number of times the given letter appears in the given sentence.
PROBLEM: Sentence: 'a man flying through the air on a bicycle'. Find frequency of the letter 'u'

SOLUTION: 1

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

SOLUTION: 4

PROBLEM: Sentence: 'a train with smoke is coming down the tracks near a building'. Find frequency of the letter 's'

SOLUTION:
3