Answer
a balance and a graduated cylinder
Explanation
Density is mass per unit and it is property characteristic of a substance. The arrangement of the mass of atoms and their size is what determines the the density of a substance.
For a student to measure the density of seawater he/she is required to use a balance and a graduated cylinder where a balance will be used to measure the mass of the mineral sample and then a graduated cylinder to determine the volume.
The data has to be verifiable by the scientific community.
Organisms breathe oxygen and drink water. Water and oxygen are nonliving things. ☺♥
One example:
Energy moves through an ecosystem through different organisms. For example, plants can absorb energy from the sun. Animals, such as grasshoppers, can eat the plants and the energy goes to them. Progressing higher up the food chain, the energy continues to transfer through different animals - grasshoppers can be eaten by mice, mice by snakes, snakes by eagles, etc. etc.
