TASK DEFINITION: In this task, you need to count the number of times the given letter appears in the given sentence.
PROBLEM: Sentence: 'a lady is standing near a luggage stand at the air port'. Find frequency of the letter 'a'

SOLUTION: 9

PROBLEM: Sentence: 'soccer players on opposite teams fight for control over a ball'. Find frequency of the letter 't'

SOLUTION: 4

PROBLEM: Sentence: 'tourists taking photos of a half-horse half-zebra playing'. Find frequency of the letter 'g'

SOLUTION:
2