Answer:
Step-by-step explanation:
When you put another light bulb in parallel with the other two, you are not going to get something for nothing. The current drain on the battery has to go up.
Let the lightbulbs have a a resistance of r. Two light bulbs with make the resistance go to 1/2 r. The lower the resistance, the more the current. When you put the third light bulb in, the resistance will go to 1/3 r. So the current goes up.
If you put another resistor in series with x, the resistance adds. The total series resistance is 2x. The current reading will go down. The higher the resistance the lower the current.