In analyzing the strain on a beam, Mohr’s circle is often used. To form it, normal strain is plotted as the x-coordinate and shear strain is plotted as the y-coordinate. The center of the circle is midway between the minimum and maximum values of normal strain on the x-axis. Find the equation of Mohr’s circle if the minimum normal strain is 100 ×10⁻⁶ and the maximum normal strain is 900 ×10⁻⁶ (strain is unitless). Sketch the graph.