Im working on science too!! I would help you but the attachment isn't pulling up..
Answer: high iridium levels in a 66- million-year-old clay layer in Denmark and Italy
Explanation:
Answer:
Chemical changes occur when a substance combines with another to form a new substance, called chemical synthesis or, alternatively, chemical decomposition into two or more different substances. These processes are called chemical reactions and, in general, are not reversible except by further chemical reactions.
Explanation:
A Anything that has mass and takes up space
