TASK DEFINITION: In this task, you need to count the number of times the given letter appears in the given sentence.
PROBLEM: Sentence: 'a child sitting a table with a pizza in front of him'. Find frequency of the letter 'h'

SOLUTION: 3

PROBLEM: Sentence: 'a small boy in a high chair eating a cupcake'. Find frequency of the letter 'i'

SOLUTION: 4

PROBLEM: Sentence: 'a baby trying to open a lap top'. Find frequency of the letter 't'

SOLUTION:
3