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

Sentence: 'a double parking meter is decorated with a picture of a girl with wings on her feet'. Find frequency of the letter 'r'
6

Sentence: 'a gray colored pigeon that is perched on a railing outside of a building, with other buildings in the background'. Find frequency of the letter 'e'
7

Sentence: 'some giraffes moving across a big grass field'. Find frequency of the letter 'e'
3