well, for the first question, you must remember the age old formula.
Watts = Volts x Amps
if you have a one
phase supply, say 120v, and it draws 15 amps, then that drill will use 1800 watts.
but
if you have a two
phase supply, like 240v, with the same size motor, it would use the same wattage but draw half the amperage, allowing you to run more things off the same
power service.
don't know about the second question, but i would guess no