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

Input: Consider Input: Sentence: 'a man pushing a cart full of bananas'. Find frequency of the letter 'u'

Output: 2

Input: Consider Input: Sentence: 'there is a person standing on a blue towel'. Find frequency of the letter 'n'

Output: 4

Input: Consider Input: Sentence: 'an empty bedroom with a bed with white sheets'. Find frequency of the letter 'h'
Output: 4