Solve the all parts of following problem:
Problem: An ammeter with a full scale deflection for I=17.0 A has an internal resistance of 18 ohms. We need to use this ammeter to measure currents up to 19.5 A. the lab instructor advises that we get a resistor and use it to protect the ammeter.
Part A: What size resistor do we need?
Part B: How should it be connected to the ammeter, in series or in parallel?
Please give a full detailed explanation of solution.