instruction:
In this task, you need to count the number of times the given letter appears in the given sentence.
question:
Sentence: 'a couple of people are sitting at a table'. Find frequency of the letter 'e'
answer:
5


question:
Sentence: 'a girl that has a kite in the air'. Find frequency of the letter 'r'
answer:
2


question:
Sentence: 'the young man is practicing his tricks on his skateboard'. Find frequency of the letter 'k'
answer:

2