Which of the statements below concerning the operation of the black light bulbs of the Mercury arc type is NOT true?

It takes about 5 minutes for the bulb to warm up to its full output when first turned on.

The lamp may go out if the line voltage drops below 90 volts.

Line voltage variations above 120 volts will have little or no effect on the bulb.

If for any reason the arc is extinguished, the bulb will not immediately respond if the lamp Is turned on right after it has been turned off.