In this task, you need to count the number of words in a sentence that start with the given letter. Answer with numbers and not words.

Example Input: Sentence: 'a person with a hoodie on looking at a laptop'. How many words start with the letter 'l' in the sentence.
Example Output: 2

Example Input: Sentence: 'two giraffes are walking down a rocky path'. How many words start with the letter 'a' in the sentence.
Example Output: 2

Example Input: Sentence: 'a room filled with a stove and surrounded by cabinets'. How many words start with the letter 'w' in the sentence.
Example Output:
1