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

[EX Q]: Sentence: 'young girl playing with refrigerator magnet while kneeling on floor'. Find frequency of the letter 'n'
[EX A]: 6

[EX Q]: Sentence: 'a bathroom with a sink, counter top, and mirror is shown'. Find frequency of the letter 'i'
[EX A]: 4

[EX Q]: Sentence: 'a large group of giraffes walking around an enclosure'. Find frequency of the letter 'n'
[EX A]:
4