Answer the following questions related to the correct use of a voltmeter.
a. (a) State how a voltmeter is connected in an electric circuit to measure the potential difference between two points.
b. (b) Explain with reason why a voltmeter is designed to have a very high resistance.
c. (c) A student by mistake connects a voltmeter in series with a resistor and a battery. Predict qualitatively what will happen to (i) the current in the circuit and (ii) the reading on the voltmeter. Give reasons for your answers.