TASK DEFINITION: In this task, you need to count the number of times the given letter appears in the given sentence.
PROBLEM: Sentence: 'a person that is looking out his window'. Find frequency of the letter 'n'

SOLUTION: 3

PROBLEM: Sentence: 'two elephants facing each other touching trunks in an enclosure'. Find frequency of the letter 'f'

SOLUTION: 1

PROBLEM: Sentence: 'a person jumping up to catch a frisbee'. Find frequency of the letter 's'

SOLUTION:
2