Substitution of Equation 7 into Equation 6 yields the pressure difference as a function of well diameter, 𝐷. This equation is valid for all quadrants of the 5-spot configuration, and the total flow rate through the well is 𝑚̇𝑡 𝑜𝑡 = 4𝑚̇, due to the symmetry of the problem. We express the impedance in terms of Δ𝑃 𝑡𝑜𝑡 and 𝑚̇𝑡 𝑜𝑡 in Equation , which leads to easier comparison with other solutions in Sec 2.1. Note that the reservoir impedance is inversely proportional to the reservoir transmissivity, 𝜅𝑏, which is the product of reservoir permeability and thickness.