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

[EX Q]: Sentence: 'the meal is served and ready to be eaten'. Find frequency of the letter 'e'
[EX A]: 8

[EX Q]: Sentence: 'a person dressed all in black snowboarding down a slope'. Find frequency of the letter 'e'
[EX A]: 4

[EX Q]: Sentence: 'a bear sits on the rocks by a pool of water in a wildlife exhibit'. Find frequency of the letter 'r'
[EX A]:
3