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

[EX Q]: Sentence: 'children with scissors and construction paper in a school classroom'. Find frequency of the letter 'c'
[EX A]: 6

[EX Q]: Sentence: 'a passenger train that is going over a bridge'. Find frequency of the letter 't'
[EX A]: 3

[EX Q]: Sentence: 'a boy standing in front of a table covered with a lot of stuff'. Find frequency of the letter 'l'
[EX A]:
2