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

Sentence: 'a person holding a wine glass in one hand and bread sticks in the other'. Find frequency of the letter 'd'
4

Sentence: 'a plane with stairs next to it sitting in a large lot'. Find frequency of the letter 'i'
6

Sentence: 'a desk and chair with a pc keyboard and  computer screen'. Find frequency of the letter 's'

2