galactic disk
The galactic disk is a thinned, leveled out distribution of stars which includes the typical to the largest and brightest. The Sun is in the Milky Way and lies amongst the majority of the stars where it bulges.
I'd say B.) Increasing the voltage of the battery.
For this case you must first know the definition of density.
D = m / v
where,
m: mass
v: volume.
You can then write the following hypothesis:
IF you know two physical characteristics of an object then you can determine the density. First weigh the object, THEN measure its volume BECAUSE the density is the quotient between the mass and the volume of an object.
So far, all we have is a very short true statement. If it's a multiple choice question, then where are they ?