instruction:
In this task, you need to count the number of times the given letter appears in the given sentence.
question:
Sentence: 'there is a sandwich with a lot of meat cut in half'. Find frequency of the letter 'a'
answer:
5


question:
Sentence: 'a man flying through the air on a bicycle'. Find frequency of the letter 'u'
answer:
1


question:
Sentence: 'a spaniel on a green sofa looking toward the camera'. Find frequency of the letter 'r'
answer:

3