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

Q: Sentence: 'a black computer with a screen reading "press any key to begin."'. Find frequency of the letter 'a'

A: 5
****
Q: Sentence: 'a dog laying on the back of a boat in the water'. Find frequency of the letter 't'

A: 4
****
Q: Sentence: 'an asian street scene with cars and people'. Find frequency of the letter 'e'

A:
6
****