Answer:
I think its B if I got it wrong at least I tried
Explanation:
have a good day
Prenatal care as well as preconception can help prevent complications and inform women about important steps they can take to protect their infant and ensure a healthy pregnancy.
First, he should measure how long it takes for the liquid to become clear if X and Y are mixed together. Then, he should measure how long it takes if he also adds substance A to X and Y. He will find out if substance A is a catalyst. hope this helps :)
