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 costume talking on a cell phone'. Find frequency of the letter 'm'
[EX A]: 2

[EX Q]: Sentence: 'the man is holding a plastic sled with snow in it next to a child'. Find frequency of the letter 'g'
[EX A]: 1

[EX Q]: Sentence: 'a jet flying high above a statue on a clock tower'. Find frequency of the letter 'o'
[EX A]:
4