The radius of the circular cross-section is 5 m. The area of one circular face is πr². When using the π button on the calculator, the area of both circular faces is 2 × π × 5² = 50π m² ...

The area of that cross section is the well known A = pi*R² which is colloquially pronounced as “pie are squared.” We will put aside the old joke that “Pie are not squared; pie are round” but we have ...

Plot a graph of resistance, R, in Ω on the y-axis against cross section area, A, in mm 2 on the x-axis. Draw the line of best fit.