In this task, you need to count the number of times the given letter appears in the given sentence.

Sentence: 'a man in a suit makes the first slice into a cake'. Find frequency of the letter 't'
4

Sentence: 'a bed with a dog laying on it next to two laptop computers'. Find frequency of the letter 'n'
3

Sentence: '3 giraffes and 3 zebras in an exhibit'. Find frequency of the letter 'a'

4