If T=const
P1V1=P2V2
P1*4L=P2*1L
P2=4P1
pressure increases by factor of 4
The given question is incomplete. The complete question is :
What is the coefficient of
when the following equation is properly balanced with the smallest set of whole numbers? 
Answer: The coefficient of
is 3
Explanation:
According to the law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side. Thus chemical equations are balanced.
The balanced chemical reaction is:

The coefficient of
is 3
Something that scientists study that is cold could be liquid nitrogen!
Below are the choices:
<span>The independent variable is the number of dry cells, and the dependent variable is the length of time the bulb works.
</span><span>The independent variable is the length of time the bulb works, and the dependent variable is the number of dry cells.
</span><span>The independent variable is the number of dry cells, and the dependent variable is the amount of energy available.
</span><span>The independent variable is the amount of energy available, and the dependent variable is the number of dry cells.
</span>
I think the answer is <span>The independent variable is the number of dry cells, and the dependent variable is the amount of energy available.</span>