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

[Q]: Sentence: 'one man grabbing another at a table while laughing'. Find frequency of the letter 'n'
[A]: 5


[Q]: Sentence: 'a man with glasses adjusting his tie in a mirror'. Find frequency of the letter 's'
[A]: 5


[Q]: Sentence: 'various people of all ages skiing at a ski lodge'. Find frequency of the letter 'r'
[A]:
1