TASK DEFINITION: In this task, you need to count the number of times the given letter appears in the given sentence.
PROBLEM: Sentence: 'a plane with smoke coming from the tips of both wings'. Find frequency of the letter 'c'

SOLUTION: 1

PROBLEM: Sentence: 'a line of people on motorcycles on the road'. Find frequency of the letter 'e'

SOLUTION: 5

PROBLEM: Sentence: 'three trains are riding on the tracks in the large city'. Find frequency of the letter 't'

SOLUTION:
6