TASK DEFINITION: In this task, you need to count the number of times the given letter appears in the given sentence.
PROBLEM: Sentence: 'two people and two children walking in a building'. Find frequency of the letter 'd'

SOLUTION: 3

PROBLEM: Sentence: 'the man is holding a plastic sled with snow in it next to a child'. Find frequency of the letter 'g'

SOLUTION: 1

PROBLEM: Sentence: 'a computer and accessories are sitting on the ground'. Find frequency of the letter 'i'

SOLUTION:
3