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

[EX Q]: Sentence: 'a gray colored pigeon that is perched on a railing outside of a building, with other buildings in the background'. Find frequency of the letter 'e'
[EX A]: 7

[EX Q]: Sentence: 'a bowl of granola with raspberries and honey on top with a spoon'. Find frequency of the letter 'w'
[EX A]: 3

[EX Q]: Sentence: 'a man on a skateboard in mid air on a city street'. Find frequency of the letter 'a'
[EX A]:
7