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.

Sentence: 'a boy in a red baseball uniform throws a ball'. How many words start with the letter 'b' in the sentence.
3

Sentence: 'bed with white blanket and two pillows with a light glowing from under and behind the bed'. How many words start with the letter 'a' in the sentence.
3

Sentence: 'two pieces of luggage on a luggage carrousel at an airport'. How many words start with the letter 'a' in the sentence.
4