instruction:
In this task, you need to count the number of times the given letter appears in the given sentence.
question:
Sentence: 'a young girl is brushing her teeth in this dated photo'. Find frequency of the letter 't'
answer:
5


question:
Sentence: 'a man is water skiing on a river'. Find frequency of the letter 'r'
answer:
3


question:
Sentence: 'one skier has fallen down while the other is standing up'. Find frequency of the letter 'e'
answer:

6