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

Sentence: 'a batter, catcher and umpire waiting for the pitch and a major league baseball game'. Find frequency of the letter 'c'
3

Sentence: 'eight donuts are cooked together in oil in a metal tray'. Find frequency of the letter 'h'
2

Sentence: 'a stone building with a clock tower on an overcast day'. Find frequency of the letter 'i'

3