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

[EX Q]: Sentence: 'a train station with a train pulling into the platform'. Find frequency of the letter 'i'
[EX A]: 6

[EX Q]: Sentence: 'a group of giraffes walk together by a hill'. Find frequency of the letter 'b'
[EX A]: 1

[EX Q]: Sentence: 'a platter with pizza has a fork and knife on it'. Find frequency of the letter 'e'
[EX A]:
2