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: 'a mother bear and her two young are crossing a shallow river'. How many words start with the letter 'a' in the sentence.
[A]: 4


[Q]: Sentence: 'a light shines on five clocks showing times in different zones'. How many words start with the letter 'f' in the sentence.
[A]: 1


[Q]: Sentence: 'a zebra standing next to a rock cave next to a pile of rocks'. How many words start with the letter 'a' in the sentence.
[A]:
3


