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 couple of buses parked on the side of the street'. Find frequency of the letter 'b'

SOLUTION: 1

PROBLEM: Sentence: 'a person relaxing on a mattress in a truck'. Find frequency of the letter 'p'

SOLUTION:
1