TASK DEFINITION: In this task, you need to count the number of times the given letter appears in the given sentence.
PROBLEM: Sentence: 'a birthday cake with a number one and three candle'. Find frequency of the letter 'w'

SOLUTION: 1

PROBLEM: Sentence: 'a mixed bouquet of flowers in a glass vase set before a window'. Find frequency of the letter 'w'

SOLUTION: 3

PROBLEM: Sentence: 'a cat is sleeping on the arm of a couch'. Find frequency of the letter 'r'

SOLUTION:
1