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

Input: Consider Input: Sentence: 'a grapefruit, toast, coffee and other items are on a tray'. Find frequency of the letter 't'

Output: 6

Input: Consider Input: Sentence: 'a group of men standing around a table cutting a cake'. Find frequency of the letter 'g'

Output: 3

Input: Consider Input: Sentence: 'a close up of a zebra next to a tree'. Find frequency of the letter 'o'
Output: 3