I NEED HELP ASAP!! 1. is Pepsi a mixture or pure substance?
2. is Sulfur mixture or pure substance?
3. is Copper penny pure or substance?

2. if scientists identify an animal with bilateral symmetry and no segmentation, which phylum can it definitely not belong to? a. roundworms b. annelids c. mollusks d. flatworms

Describe the response the kidneys have to dehydration and excessive water intake. what happens to the concentration of urine in each case ?

What would be the result if crossing over did not happen during meiosis in humans? a. there would be less genetic variation in humans. b. parents would be more likely to look like their children. c. the human population could not reproduce. d. children would have more chromosomes.