In this task, you need to count the number of times the given letter appears in the given sentence.

Q: Sentence: 'men are riding on motorcycles with a man riding in their carriers'. Find frequency of the letter 'r'

A: 8
****
Q: Sentence: 'a large bathroom with marble floor, counter, and bath'. Find frequency of the letter 'f'

A: 1
****
Q: Sentence: 'a small dog walking on a lonely beach'. Find frequency of the letter 'o'

A:
3
****