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

Sentence: 'a family out snow skiing on a blustery day'. Find frequency of the letter 'i'
3

Sentence: 'a train going over a bridge with some buildings in the background'. Find frequency of the letter 'd'
3

Sentence: 'the man is happy that he has found the view'. Find frequency of the letter 'h'

6