TASK DEFINITION: In this task, you need to count the number of times the given letter appears in the given sentence.
PROBLEM: Sentence: 'a softball player holding the bat on first base'. Find frequency of the letter 't'

SOLUTION: 4

PROBLEM: Sentence: 'an old glass vase containing flowers on a glass table'. Find frequency of the letter 'b'

SOLUTION: 1

PROBLEM: Sentence: 'a large mirror sitting on a subway platform'. Find frequency of the letter 'b'

SOLUTION:
1