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.

[Q]: Sentence: 'two couples sit on a bench in front of bushes with pink flowers'. How many words start with the letter 'o' in the sentence.
[A]: 2


[Q]: Sentence: 'a skateboarder doing a trick at a skate park'. How many words start with the letter 'a' in the sentence.
[A]: 4


[Q]: Sentence: 'a street scene with skateboard rails and ramps'. How many words start with the letter 's' in the sentence.
[A]:
3