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: 'children with scissors and construction paper in a school classroom'. Find frequency of the letter 'c'

Output: 6

Input: Consider Input: Sentence: 'a couple of cellphones are laying out together'. Find frequency of the letter 't'
Output: 3