1. elliptical 2. solar system
Oxygen has a partial negative charge, whereas hydrogen had a partial positive charge.
This means that water molecules are polar and can be used to dissolve a lot of chemicals, that's why water is such a popular solvent.
Answer:
At the bottom you have the producers aka auto trophic livings (which use inorganic compounds to grow, produce energy, matter and so on..). These organisms would be plants, Cyrano bacteria, over all any organisms that do photosynthesis.
Brain size has increased nearly 3x in 4 million years.
Albert, a student researcher, varies the amount of food given to rats in an experiment to measure the effect on their learning behavior. In albert's study, the amount of food given is the independent variable.
An independent variable is under the control of the experimenter. Independent variable does not depend on the other variables involved in the experiment. Since the amount of food is varied, it is not depending on other variables like size of mice, weight, etc.
