instruction:
In this task, you need to count the number of times the given letter appears in the given sentence.
question:
Sentence: 'a man that is on his cell phone'. Find frequency of the letter 's'
answer:
2


question:
Sentence: 'a fluffy white car looking in a mirror'. Find frequency of the letter 'k'
answer:
1


question:
Sentence: 'a room showing a cooker and an oven'. Find frequency of the letter 'd'
answer:

1