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

[Q]: Sentence: 'a man paddle boarding by a boat dock in a city'. Find frequency of the letter 'o'
[A]: 3


[Q]: Sentence: 'girls posing of a picture one holding a tennis racket the other wearing a crown'. Find frequency of the letter 'g'
[A]: 4


[Q]: Sentence: 'a clock showing its inner workings through a glass fronted case'. Find frequency of the letter 'o'
[A]:
5