What is the total strain energy (in kcal/mol) of the least stable (highest energy) conformation possible for 2,3-dimethylbutane? All of the choices below are expressed in units of kcal/mol.
A. 0 B. 0.9 C. 1.8 D. 2.7 E. 3.4
F. 3.6 G. 4.4 H. 5.8 I. 7.2 J. None of these