TASK DEFINITION: In this task, you need to count the number of times the given letter appears in the given sentence.
PROBLEM: Sentence: 'black and white photograph of man and woman sitting on a bench'. Find frequency of the letter 'w'

SOLUTION: 2

PROBLEM: Sentence: 'a black bear sitting in the grass taking a rest'. Find frequency of the letter 'a'

SOLUTION: 6

PROBLEM: Sentence: 'this is a child on a bench with a toilet in the background'. Find frequency of the letter 'e'

SOLUTION:
3