TASK DEFINITION: In this task, you need to count the number of times the given letter appears in the given sentence.
PROBLEM: Sentence: 'a crowd of people skiing and enjoying the snow'. Find frequency of the letter 'o'

SOLUTION: 5

PROBLEM: Sentence: 'a herd of giraffes in tall african grass'. Find frequency of the letter 'a'

SOLUTION: 6

PROBLEM: Sentence: 'a flatbed truck and some parked cars and buildings'. Find frequency of the letter 'n'

SOLUTION:
3