Answer: TWO.
At least two groups: treatment group and control group.
The treatment group is that is exposed to the different levels of the independent variable ( a medication for example), while the control group is not treated, so the researchers can compare the effect of the medication.
When an entire species perishes the species becomes extinct.
The correct response is C. Chlorine forms 1 covalent bond while Oxygen forms 2 covalent bonds.
Answer:
a
. eight tenths of her cookies
Explanation:
Let the total number of Lakesha's cookies be represented by x.
So that;
She gave three tenths to Bailey =
of x
= 
She gave five tenths to Helen =
of x
= 
Fraction of Lakesha's cookies given away =
+ 
= 
= 
Thus, the fraction of cookies given away by Lakesha is
.
526 L O2 x 1 mol O2 / 22.4 L = 23.5 mol O2