The carbon cycle is the biogeochemical cycle by which carbon is exchanged among the biosphere, pedosphere, geosphere, hydrosphere, and atmosphere of the Earth. Carbon is the main component of biological compounds as well as a major component of many minerals such as limestone.
The well - designed experiment test one factor at a time. The answer to the question above is letter A. 1. The items that are being tested are the independent variables and that they cause the dependent variables to change.
Answer:
Spread
Explanation:
People use envelopes very often. The germs people carry are put into the envelope and then it's sent out to many others.
