Help with some Physics questions that I don't understand. Plz help, Thank you and 10points best answer! =)

Thank you so much! Even if you only answer one question, that's fine & 10 points best answer!! =D
1.). If you used batteries that each have 1.5 volts, how would connecting two batteries in series affect the brightness of the bulb compared to a single battery? How would two batteries in series affect the current flowing through the circuit?
2.)The electrical potential energy of the charges flowing in a circuit converted into other kinds of energy. What kinds of energy is the electrical potential energy being converted into?

1) The volts add up; the voltage doubles; the current doubles.

The bulb would dissipate 4 times the power (voltage and current both double, power = volts times current) and thus be brighter.

2) Depending on what the circuit contains, electrical energy can be converted into mechanical energy, light, sound or heat.

Batteries connected in series increases the voltage. So two batteries of 1.5V each means a total voltage of 1.5+1.5=3V. the bulb will have a constant resistance. current in the circuit is given by I=V/R. SO if V increases and R doesn't change, the current will increase. But if the bulb is rated for only 1.5V, applying 3V to it might damage it.
The electrical potential energy is mainly converted to heat and magnetism. A wire carrying current has a magnetic field around it and no matter how less, it will dissipate energy in the form of heat.
I hope I have managed to answer your question :-)