Plot a graph of V as ordinate against I as abscissa and calculate its slope (2).

Here are the answers to the questions based on the provided image and context:

11. Plot a graph of V as ordinate against I as abscissa.
To plot this graph, experimental data for terminal voltage ($V$) and current ($I$) is required. Since no data is provided in the image, a specific plot cannot be generated. In a real experiment, you would plot the recorded values of $V$ on the y-axis and $I$ on the x-axis. The expected graph would be a straight line with a negative slope.

12. Calculate the slope ($\alpha_2$) of the graph.
Assuming a graph of $V$ versus $I$ has been plotted, the slope ($\alpha_2$) would be