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

[EX Q]: Sentence: 'a man opening up a package sitting on a couch'. Find frequency of the letter 'n'
[EX A]: 5

[EX Q]: Sentence: 'a wedding cake with pink roses on a silver plate'. Find frequency of the letter 'a'
[EX A]: 4

[EX Q]: Sentence: 'a two lane road with a crane travelling in one lane'. Find frequency of the letter 'g'
[EX A]:
1