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 bed sitting next to a window with a wooden headboard'. How many words start with the letter 'a' in the sentence.
Example Output: 3

Example Input: Sentence: 'a statue holding a red umbrella in a pond'. How many words start with the letter 's' in the sentence.
Example Output: 1

Example Input: Sentence: 'a woman in a black top is talking on a cellphone'. How many words start with the letter 'a' in the sentence.
Example Output:
3