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

Q: Sentence: 'group of snowboarders on a snowy trail overlooking a mountain'. Find frequency of the letter 'r'

A: 5
****
Q: Sentence: 'two men are playing a video game as another sits watching'. Find frequency of the letter 'a'

A: 7
****
Q: Sentence: 'three boys with skateboards practicing their moves on asphalt'. Find frequency of the letter 'i'

A:
4
****