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

Sentence: 'a birthday cake with a number one and three candle'. Find frequency of the letter 'w'
1

Sentence: 'a person on a sidewalk jumping with an umbrella'. Find frequency of the letter 'a'
5

Sentence: 'a man with his mouth open holds a hot dog and a dollar bill'. Find frequency of the letter 'h'

5