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

[EX Q]: Sentence: 'a tennis player after hitting a shot back to the other side of the court'. Find frequency of the letter 'n'
[EX A]: 3

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

[EX Q]: Sentence: 'a pizza is in a box on a table outside'. Find frequency of the letter 'u'
[EX A]:
1