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

Q: Sentence: 'two men sitting quietly on a park bench'. Find frequency of the letter 'a'

A: 2
****
Q: Sentence: 'a young girl skiing down a snowy mountain'. Find frequency of the letter 'l'

A: 1
****
Q: Sentence: 'single train car out on the tracks by some trees'. Find frequency of the letter 'k'

A:
1
****