TASK DEFINITION: In this task, you need to count the number of times the given letter appears in the given sentence.
PROBLEM: Sentence: 'a wedding cake with pink roses on a silver plate'. Find frequency of the letter 'a'

SOLUTION: 4

PROBLEM: Sentence: 'baseball player reaching back as he's about to throw the ball'. Find frequency of the letter 'e'

SOLUTION: 5

PROBLEM: Sentence: 'a kitchen has a sink and a oven in it'. Find frequency of the letter 't'

SOLUTION:
2