TASK DEFINITION: In this task, you need to count the number of times the given letter appears in the given sentence.
PROBLEM: Sentence: 'a girl laying on a bed posing for a picture'. Find frequency of the letter 'i'

SOLUTION: 4

PROBLEM: Sentence: 'a man on stiltz is standing under a pink umbrella'. Find frequency of the letter 's'

SOLUTION: 3

PROBLEM: Sentence: 'a bathroom with a sink and a mirror'. Find frequency of the letter 'h'

SOLUTION:
2