Suppose that you have a rod that is positively charged, a rod that is negatively charged and a stand that allows rotation. if you are handed a rod of unknown charge-state, could you determine if it has a positive charge, a negative charge or if it is neutral? explain

Yes, you can. Remember that in electrophysics, opposite charges attract. Since there is a stand of rotation, it allows the rod with both ends having opposite charges to rotate. Now, if you place the unknown charge near the set-up, it could turn clockwise or counterclockwise. When the set-up turns such that the negative end is approaching the unknown charge, that charge must be positive. Otherwise, the unknown charge is negative.