TASK DEFINITION: In this task, you need to count the number of times the given letter appears in the given sentence.
PROBLEM: Sentence: 'an airplane is being towed away from the jet bridge'. Find frequency of the letter 's'

SOLUTION: 1

PROBLEM: Sentence: 'a flock of sheep grazing in a park'. Find frequency of the letter 'f'

SOLUTION: 2

PROBLEM: Sentence: 'a frontier airplane sits in an airplane hangar'. Find frequency of the letter 'r'

SOLUTION:
5