This is because elements are pure substances with only one atom. When two or more elements are combined, you get compound elements; which allows for more substances to be created.
Dogs, no matter what breed they are, they are all of the same species and therefore can breed with each other and create fertile offspring
I pray this helps you :)
A phenomenon, in the scientific context, is an observable event that can range from a seasonal hazard to a technological issue. For a scientist, a phenomenon is an observable event.
List three characteristics of living organisms