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

Q: Sentence: 'a group of three dogs laying on a kitchen floor'. Find frequency of the letter 'r'

A: 3
****
Q: Sentence: 'a dog laying on the back of a boat in the water'. Find frequency of the letter 't'

A: 4
****
Q: Sentence: 'a woman walking with an umbrella in the sun'. Find frequency of the letter 'n'

A:
5
****