electric circuit ~

1. Since the emf is constant, according to V=IR, when R tends to infinity (in a voltmeter), I tends to zero. And emf of a battery = terminal voltage + voltage across internal resistance. Since I tends to 0, voltage across internal resistance tends to 0. Therefore, the reading= emf = terminal voltage in that circuit.

2. It means.... in parallel or in series. It is not clearly stated.

But, in common usage, this would mean in parallel.

1. If you connected the voltmeter in series and the connecting wire has resistance, the voltmeter can measure the terminal voltage of the circuit because there are the voltage drop of the connecting wire.

2. If it is the test of the voltage drop in resistor, you should connect the voltmeter in parallel with resistor. If you just measure the emf of cell, you can connect the voltmeter in series to the cell.