instruction:
In this task, you need to count the number of times the given letter appears in the given sentence.
question:
Sentence: 'a man serving himself pizza in a wooden booth'. Find frequency of the letter 'n'
answer:
4


question:
Sentence: 'hand holding a white calculator inside a store'. Find frequency of the letter 'o'
answer:
3


question:
Sentence: 'two young men wearing black and white suits posing for a photo'. Find frequency of the letter 'k'
answer:

1