TASK DEFINITION: In this task, you need to count the number of times the given letter appears in the given sentence.
PROBLEM: Sentence: 'a piece of meat covered in ketchup next to a hamburger on a green plate'. Find frequency of the letter 'g'

SOLUTION: 2

PROBLEM: Sentence: 'an old boat on a beach near a large body of water'. Find frequency of the letter 'a'

SOLUTION: 8

PROBLEM: Sentence: 'there is a mirror and trash can and a mirror with two cats nearby'. Find frequency of the letter 'i'

SOLUTION:
4