TASK DEFINITION: In this task, you need to count the number of times the given letter appears in the given sentence.
PROBLEM: Sentence: 'a cat sprawls out and sleeps on its back on a lounge chair with an acorn theme'. Find frequency of the letter 'r'

SOLUTION: 3

PROBLEM: Sentence: 'a yellow and green train on a train track in a wooded area'. Find frequency of the letter 'o'

SOLUTION: 4

PROBLEM: Sentence: 'baseball ball pitcher getting ready to throw the ball'. Find frequency of the letter 'b'

SOLUTION:
4