TASK DEFINITION: In this task, you need to count the number of times the given letter appears in the given sentence.
PROBLEM: Sentence: 'a woman at a table checking her cell phone'. Find frequency of the letter 'a'

SOLUTION: 5

PROBLEM: Sentence: 'a double decker transit bus parks by a blue on the side of the street in front of a brick building in the city'. Find frequency of the letter 't'

SOLUTION: 9

PROBLEM: Sentence: 'an elephant on a grassy field during the day'. Find frequency of the letter 'o'

SOLUTION:
1