I need the answer in C code not C++

Problem Statement Your company manufactures electrically conductive metal bars with custom polygonal cross sections. The metal extrusion machine is limited to producing metal bars with a four-sided polygon as the cross-section. You are given the assignment to calculate the electrical resistance of the bar given its cross-section shape, length, and type of metal. Background Pi Arbitrary Cross-section The DC resistance of a conductor having a length L and a uniform cross-sectional area A is given by this equation: where is the electrical conductivity of the conductor. Table I shows the conductivity of common metals used in electrical wires. Table 1: Metal electrical conductivity Conductor Silver Copper Gold Aluminum Platinum Conductivity (S/m) 6.30x10 5.96x 0' 4.10x10 3.50x107 0.943x10