<span>7 electrons in each outer shell
Group 17
Most reactive
Fluorine, Chlorine, Bromine, Iodine, Astatine
Alkali Metals:
1 electron is each outer shell
Group 1
Also reactive, but not as much as the halogens
Lithium, Sodium, Potassium, Rubidium, Cesium, Francium </span>
Answer:
C. Independent variable
Explanation:
The independent variable in an experiment is the variable that the experimenter manipulates or changes in order to effect a measurable response in the dependent variable.
According to this question, an experiment is conducted to determine what concentration of disinfectant is most effective in killing bacteria. The independent variable is the CONCENTRATION OF DISINFECTANT because it is the variable being changed or manipulated.
A courtship dance or mating ritual hope this helped
---C---- if brown snails are mostly eaten that most likely means they are more common. If less than snails are eaten then stripedsnails would eventually over populate brown snails and then brown snails would overpopulate striped snails ..... so elminate b and d and snails probably won't go extinct..... so I would have to go with c