a. For each, note if any total eclipse" steric interactions exist (two non-hydrogens eclipsing) b. For each, note if any "gauche" steric interactions exist (two non-hydrogens gauche) 7. 8. 9. 11. 12. H H 10. H H 13. H H H CH3 F CH3 CH3 HC H CH3 H H CH3 H H3C, H H CH3 H H H iPr IH H H CH3 H H H H CH3 CH3 iPr H CH3 H H H H H H H H H H CH H CH3 H CH3 H CHH3 CH3 CH3 TH H CH3 iPr H H CH iPr CH CH CH CH3 CH3