TASK DEFINITION: In this task, you need to count the number of times the given letter appears in the given sentence.
PROBLEM: Sentence: 'salad and vegetables with me on top of plate'. Find frequency of the letter 'o'

SOLUTION: 3

PROBLEM: Sentence: 'a grapefruit, toast, coffee and other items are on a tray'. Find frequency of the letter 't'

SOLUTION: 6

PROBLEM: Sentence: 'a new york yankees player stands on the ball field'. Find frequency of the letter 's'

SOLUTION:
3