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

[Q]: Sentence: 'a car accident has slowed traffic as a clean up crew works'. Find frequency of the letter 'f'
[A]: 2


[Q]: Sentence: 'two people holding their skies in a snowy resort'. Find frequency of the letter 'n'
[A]: 3


[Q]: Sentence: 'antique black and white photograph of people with horses outside a barn and grain tower'. Find frequency of the letter 'u'
[A]:
2