- 8.G.C.9:Solve real-world and mathematical problems involving volume of cylinders, cones, and spheres. Know the formulas for the volumes of cones, cylinders, and spheres and use them to solve real-world and mathematical problems. (8.EE.2 Students solve simple cube root equations of the form x3 = p that arise from the volume problems. 8.NS.2 Students understand that pi is an irrational number and approximate irrational numbers that arise in volume as problems as appropriate)*