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

[EX Q]: Sentence: 'a stuffed animal sitting on an empty bed'. Find frequency of the letter 'u'
[EX A]: 1

[EX Q]: Sentence: 'a large motorcycle that has a man dressed in old clothing next to it'. Find frequency of the letter 'a'
[EX A]: 6

[EX Q]: Sentence: 'two men with colorful ties are posing for a picture'. Find frequency of the letter 'r'
[EX A]:
4