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

Sentence: 'a stuffed animal sitting on an empty bed'. Find frequency of the letter 'u'
1

Sentence: 'a red train traveling down train tracks near a forest'. Find frequency of the letter 'f'
1

Sentence: 'a delivery truck and a couple of bikes'. Find frequency of the letter 'y'

1