TASK DEFINITION: In this task, you need to count the number of times the given letter appears in the given sentence.
PROBLEM: Sentence: 'a man is taking a picture of a man and woman'. Find frequency of the letter 'a'

SOLUTION: 8

PROBLEM: Sentence: 'a plastic plastic plate topped with three different type of food'. Find frequency of the letter 'l'

SOLUTION: 3

PROBLEM: Sentence: 'two covered signs, one being a stop sign are standing alone'. Find frequency of the letter 's'

SOLUTION:
5