If the voltage impressed across a circuit is held constant while the resistance doubles, what change occurs in the current?

The current halves

Explanation:

The relationship between voltage, current and resistance in a circuit is given by Ohm's law:

where

V is the voltage

R is the resistance

I is the current

We can rewrite the formula as

we see that I is directly proportional to V and inversely proportional to R.  In this problem, V is held constant while R is doubled:

so, the new current in the circuit will be

So, the current halves.

hotter stars = bluer stars

i guess that visual aids present persuasive examples to what you are presenting, some factors would be theme (does it fit with the color, information, what you are presenting), size (can you see it, is it a big enough span of data/information), and overall look of the visual aid.

hope this : )