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

[EX Q]: Sentence: 'a glass bowl of raw broccoli, a ceramic bowl of raw green chili peppers, and steel bowl of raw daikon'. Find frequency of the letter 'a'
[EX A]: 9

[EX Q]: Sentence: 'the large modern train is on the train track'. Find frequency of the letter 'm'
[EX A]: 1

[EX Q]: Sentence: 'a bunch of people are standing out in a field a red one has their arms out as a white ball is in the air'. Find frequency of the letter 'e'
[EX A]:
9