TASK DEFINITION: In this task, you need to count the number of times the given letter appears in the given sentence.
PROBLEM: Sentence: 'a large grass pasture land with sheep grazing on grass'. Find frequency of the letter 'a'

SOLUTION: 7

PROBLEM: Sentence: 'a tennis player after hitting a shot back to the other side of the court'. Find frequency of the letter 'n'

SOLUTION: 3

PROBLEM: Sentence: 'a doll holds a cup of coffee and brushes her teeth'. Find frequency of the letter 'b'

SOLUTION:
1