i really have no clue how to do these. they seem more conceptual. any hints would be welcome! thanks! 1. Prove that when n identical resistors of resistance R are connected in parallel the equivalent resistance is R/n. 2. A piece of copper wire of resistance R is cut into 3 equal parts. When these 3 parts are connected in parallel, what is the resistance of the combination? 3. Say you have a series and parallel circuit. Resistors 2 and 3 are parallel to each other. Resistor 1 is in series with them. When you increase the resistance of 3, what happens to current and voltage values? Thanks!