build a cicuit that must be able to operate a 3 amp load of the LED while being able to operate at voltages around 3V or 6V. It must be able to keep the LED on constantly while also being able to pulse the LED. Try not to use any resistors/voltage regulators or the such that that just turn the extra energy to heat ex( a 5V voltage regulator turns all the energy about 5V to heat in order to have a stable output of 5V)