Is a group of related objects that interact with each other and
nhysics, a
form a complex whole.

The freezing and boiling point of a substance changes as the air pressure around it changes. for example, at a lower air pressure (higher altitude) it is easier for water molecules to escape from liquid into the air. in a high altitude city such as denver, colorado compared to a sea-level city such as houston, texas, water

Can you match these to the correct definition

Coal contains energy. a. light b. kinetic c. chemical d. mechanical