Answer:
A
Explanation:
Early groups of hunter gatherers continued to move south. They would eventually settle down in areas such as central america, with civilizations such as the Aztecs and the Mayans.
Explanation:
The small number behind each element symbol designates the number of atoms of each element in a chemical formula. If there is no number, it is assumed there is only one of those elements. A large number designates how many units there are of that compound.
Answer:
Control group: volunteer stationary bike riders in a pollution-free chamber
Experimental group: volunteer stationary bike riders in a chamber filled with air pollutants common to Los Angeles
Independent variable: exposure to air pollution
Dependent variable: The heart rates (physical fitness) of the volunteer riders.
Explanation:
In a scientific experiment, data is compared between the control group and experimental group to ascertain the effect of the independent variable on the dependent variable. A control group is the group in an experiment that is not treated with the independent variable i.e. the independent variable is controlled while the experimental group is the group that is treated with an independent variable.
N.B: The independent variable is the variable controlled by the experimenter in order to influence the dependent variable (measurable outcome).
In this experiment, the independent variable is the AIR POLLUTION the volunteer riders are exposed to while the dependent variable is the PHYSICAL FITNESS/ HEART RATES of the volunteer riders, which is dependent on the exposure to air pollution (independent variable).
The control group in this experiment is the volunteer riders placed in a POLLUTION-FREE CHAMBER where the independent variable cannot influence or have any effect on the measurable variable (dependent). The experimental group is the volunteer riders placed in a CHAMBER FILLED WITH AIR POLLUTANTS. The independent variable (air pollution) has been changed in the experimental group.
Answer: A. Inner Core
Explanation: The inner core is solid, the outer core is liquid, and the mantle is solid/ plastic. This is due to the relative melting points of the different layers (nickel - iron core, silicate crust and mantle) and the increase in temperature and pressure as depth increases. Hope this helps :) If not, I am sorry :( If it does, Your Welcome!