TASK DEFINITION: In this task, you need to count the number of times the given letter appears in the given sentence.
PROBLEM: Sentence: 'a bowl of granola, dried fruit, and bananas'. Find frequency of the letter 'u'

SOLUTION: 1

PROBLEM: Sentence: 'three young people goofing around; one of the guys has a football, the girl has a teddy bear'. Find frequency of the letter 'd'

SOLUTION: 3

PROBLEM: Sentence: 'a dog sitting on a bed wagging its tail'. Find frequency of the letter 's'

SOLUTION:
2