instruction:
In this task, you need to count the number of times the given letter appears in the given sentence.
question:
Sentence: 'a blue train on a track next to another track'. Find frequency of the letter 'c'
answer:
2


question:
Sentence: 'a teddy bear is sitting on a heart shaped patio chair outside'. Find frequency of the letter 'i'
answer:
6


question:
Sentence: 'three people on a raft going over a small waterfall'. Find frequency of the letter 'n'
answer:

2