Click the mouse on the molecule to view the favored structures.

In the original drawing, the two methyl groups are axial; the most stable conformation will have both groups equatorial.

The original drawing is a "boat" conformation. First you should convert this to a chair by rotating one end downward. In this chair, one methyl group is axial and the other is equatorial, which is the most stable conformation for this molecule.

In the original drawing, the tert-butyl group and the two methyl groups are axial; the most stable conformation will have all groups equatorial.

In the original drawing, both bromines are axial; the most stable conformation will have both groups equatorial.

The ring junction in this molecule is trans, therefore the molecule is simply two cyclohexane rings fused 1,2-trans (look at the hydrogens).

The ring junction in this molecule is cis, therefore the molecule is simply two cyclohexane rings fused 1,2-cis (look at the hydrogens).

The ring junction in this molecule is trans, therefore the molecule is simply two cyclohexane rings fused 1,2-trans; this, however, places the tert-butyl group in an axial position, which is energetically disallowed. To compensate for this, the second ring assumes a "boat" conformation, in which the tert-butyl group can be "axial-like".

All of the ring junctions in this molecule are trans, therefore the molecule is simply three cyclohexane rings fused trans (look at the hydrogens).

The cyclohexane is the parent; the two bromines are 1,2 relative to each other and the stereochemistry is trans (E).