The V-I graph of three resistors

Three resistors, of $6\ \Omega$, $11\ \Omega$ and $22\ \Omega$, are each joined to voltages from $0$ to $12\ \text{V}$. You will make the program find the current through each at $12\ \text{V}$, name the resistor that carries the most, and get a resistance back from the slope of a V-I line. Then it draws the three V-I lines.

Your tasks.

1. Inside the loop, work out I12, the current through the resistor R at $12\ \text{V}$.
2. Find most, the resistance that carries the largest current at $12\ \text{V}$.
3. Find slope, the slope of the V-I line from the two points (I_a, V_a) and (I_b, V_b).