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.

[EX Q]: Sentence: 'there is a lap top on a desk at a office'. How many words start with the letter 'o' in the sentence.
[EX A]: 2

[EX Q]: Sentence: 'a man is sitting on his motorcycle outside'. How many words start with the letter 'o' in the sentence.
[EX A]: 2

[EX Q]: Sentence: 'a man on the field dropped a racket and walks'. How many words start with the letter 'a' in the sentence.
[EX A]:
3