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

Sentence: 'a bunch of green bananas is hanging on a tree'. Find frequency of the letter 'n'
7

Sentence: 'guy leans on truck's hood while taking pics next to parked motorcycles'. Find frequency of the letter 's'
4

Sentence: 'two laptop computers sitting on top of a white table'. Find frequency of the letter 'f'

1