instruction:
In this task, you need to count the number of times the given letter appears in the given sentence.
question:
Sentence: 'three elephants walk up a dirt trail from the water'. Find frequency of the letter 'l'
answer:
3


question:
Sentence: 'a cooked pizza on a silver platter with another in the background'. Find frequency of the letter 'e'
answer:
5


question:
Sentence: 'a boy wowing at a giant iced donut cake with sprinkles'. Find frequency of the letter 'n'
answer:

4