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

Input: Consider Input: Sentence: 'a bunch of fruit sitting in a bowl, its overflowing'. Find frequency of the letter 't'

Output: 4

Input: Consider Input: Sentence: 'a group of people are playing soccer on a beach'. Find frequency of the letter 'l'

Output: 2

Input: Consider Input: Sentence: 'cows standing together outside of a thatched roof building'. Find frequency of the letter 'u'
Output: 2