1.A sample has a mass of 15 g and a volume of 3 mL. Calculate the density.

5 g/mL

Explanation:

The density of a substance can be found by using the formula

From the question

mass = 15 g

volume = 3 mL

We have

We have the final answer as

5 g/mL

Hope this helps you.

The population of unionid mussels decreased after zebra mussels were introduced. zebra mussels competed with the unionid mussels for food. the zebra mussels were able to displace the unionid mussels, allowing the zebra mussel population to increase  over the years. the unionid mussel population decreased because  of lack of food.