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

[EX Q]: Sentence: 'a man in a sweatshirt is taking his own picture'. Find frequency of the letter 'u'
[EX A]: 1

[EX Q]: Sentence: 'a teddy bear is sitting on a heart shaped patio chair outside'. Find frequency of the letter 'i'
[EX A]: 6

[EX Q]: Sentence: 'a close up of a young person in a bed'. Find frequency of the letter 'e'
[EX A]:
3