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

[EX Q]: Sentence: 'a doll with huge eyes and black hair with blunt bangs holds a red umbrella'. Find frequency of the letter 'e'
[EX A]: 5

[EX Q]: Sentence: 'a yellow and green train on a train track in a wooded area'. Find frequency of the letter 'o'
[EX A]: 4

[EX Q]: Sentence: 'a snowboarder is jumping off the edge of a rail'. Find frequency of the letter 'j'
[EX A]:
1