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

[Q]: Sentence: 'hotel towels with sunglasses perched and hotel business cards and catalog'. Find frequency of the letter 'o'
[A]: 4


[Q]: Sentence: 'a train is sitting at a train station'. Find frequency of the letter 'r'
[A]: 2


[Q]: Sentence: 'a group of boys and men stand next to a plow pulled by horses'. Find frequency of the letter 't'
[A]:
3