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

Input: Consider Input: Sentence: 'a young woman dressed in green and black operating a remote control'. Find frequency of the letter 'r'

Output: 5

Input: Consider Input: Sentence: 'a young girl is brushing her teeth in this dated photo'. Find frequency of the letter 't'

Output: 5

Input: Consider Input: Sentence: 'the people are sampling wine at a wine tasting'. Find frequency of the letter 'i'
Output: 4