Two confusing questions :( Hello, I have two questions but i'm getting confused with them. Can someone help me please ? ____ 1) A structural I beam is made of steel. A view its cross-section and its dimensions are shown in: http://web.csuchico.edu/~ma260/physics/phys.jpg The density of the steel is 7.56 * 10^3 kg/m^3. (a) What is the mass of a section 1.50 m long ? (b) Assume that the atoms are predominantly iron, with atomic mass 55.9 u. How many atoms are in this section ? ____ 2) The picture in http://web.csuchico.edu/~ma260/physics/phys2.JPG shows a frustrum of a cone. Of the following mensuration (gecometrical) expressions, which describes: (a) The total circumference of the flat circular faces. (b) The volume. (c) The area of the curved surface ? (i) pi(r1 + r2) [h^2 + (r1 - r2)^2]^1/2 (ii) 2pi(r1 + r2) (iii) pi * h(r1^2 + r1r2 + r2^2) ____ Thank you.