TASK DEFINITION: In this task, you need to count the number of times the given letter appears in the given sentence.
PROBLEM: Sentence: 'pedestrian in stripe clothing standing on street corner'. Find frequency of the letter 's'

SOLUTION: 4

PROBLEM: Sentence: 'a bus is driving on the street behind some cars'. Find frequency of the letter 'a'

SOLUTION: 2

PROBLEM: Sentence: 'a woman with a bun on a plate on top of some food in a bucket'. Find frequency of the letter 'h'

SOLUTION:
1