Make sure the boxes for 'Focal Points', 'Virtual Image', and 'Labels' toward the bottom right are all checked. Set the radius of curvature to 150 cm. Choose either 'Concave' or 'Convex' depending on the chart. Change the measure of the diameter to the given values. Using the horizontal ruler from the top right of the page, measure the distance from the focal point ('F') to the front of the mirror - we call this the 'Focal Length'. Don't worry about the location of the object for this part