I need help please ASAP.

Match term definition ellipse a) diagonal cross section of a cylinder circle b) diagonal cross section through the widest part of a sphere sphere c) cross section parallel to the base of a cone great circle d) shape created when a semi-circle is rotated around the y-axis triangle e) perpendicular cross section of a cone

Which of the following observations indicates that there is a small, dense, positively charged part in the center of an atom? some uncharged particles are scattered by a gold foil. all uncharged particles are attracted towards a gold foil. all positively charged particles pass straight through a gold foil. some positively charged particles bounce back from a gold foil.

The bond energy for the van der waals bond between two helium atoms is 7.9×10−4ev. assuming that the average kinetic energy of a helium atom is (3/2)kbt, at what temperature is the average kinetic energy equal to the bond energy between two helium atoms