The unusual molecule [2.2.2] propel-lane is pictured in the margin. On the basis of the given structural parameters, what hybridization scheme best describes the carbons marked by asterisks? (Make a model to help you visualize its shape.) What types of orbital's are used in the bond between them? Would you expect this bond to be stronger or weaker than an ordinary carbon-carbon single bond (which is usually 1.54 A long)?