Chemichal is like you burn wood I can't get it back u bake a cake you cant get the eggs the milk and all that stuff back && physical is I really don't know a good example but it's the opposite of that
Answer:
There are many methods used by the scientists to study the change of earth's atmosphere and climate over the past million years. The study is called paleoclimatology. Since there are no measurement tools during those era, it studies the past by using proxy data. Proxy data includes earth's sediments, tree rings, historical archives, ice cores, and etc.
Explanation:
Birds and mammals independently evolved four-chamber hearts
Answer:
coordinated regulation of a group of genes that encode proteins with a common function.
