TASK DEFINITION: In this task, you need to count the number of times the given letter appears in the given sentence.
PROBLEM: Sentence: 'an elephant with broken tusks stands in front of a hill and boulders'. Find frequency of the letter 'n'

SOLUTION: 7

PROBLEM: Sentence: 'a closet with a fan, luggage and various boxes'. Find frequency of the letter 'a'

SOLUTION: 6

PROBLEM: Sentence: 'two giraffe stand near a tall metal fence'. Find frequency of the letter 'l'

SOLUTION:
3