The answer is The law of ''gravity'' helps explain why the density of air as the altitude above earth's surface increases.
An astronomical unit (AU) is the approximate distance from the earth to the sun. The answer is D.
Answer:
research question: how do different humidity levels affect the heights of different types of trees
independent variable: humidity level
dependent variable: tree height
constants: temperature, light, duration of time
control group: tree left outside in normal conditions
Explanation:
Cancers are said to be caused by genetics, meaning the disease originated from the DNA structure. There are viruses that affect the DNA. Examples are hepatitis B virus, Epstein-Barr virus, herpes virus-8 and human papilloma virus. These are the DNA viruses that could cause cancer.
