On the island of Hawaii, Keanu notices that the sand on the beach is black, the same color as the rock formations on the island. Keanu realizes the sand used to be part of the rock formations. How did material from the rock formations turn into sand? a

Rays from the sun shone down on the rock, and it broke into pieces.

b

If anything were left out for a long time, it would break into small pieces.

c

The sand was formed by earthquakes, tsunamis, and other natural disasters. These disasters were strong enough to break the rock into small pieces.

d

Wind and rain interacted with the rock, breaking it into small pieces.

For cyclohexane compounds drawn in a chair conformation:   -axial bonds are vertical  -equatorial bonds are parallel to two bonds within the ring.  thus, as i assume the chair conformation is drawn:   -the x group is in an axial position, as are the five other vertical bonds.  -three axial bonds are on the top face of the ring  -the other three axial bonds are on the bottom face  the position of the second substituent on each ring carbon is equatorial.  gauche groups must be on an adjacent carbon such as carbon 6 and carbon 2, and also gauche groups are rotated by 60 degrees relative to each other.  drawing the newman projections for c1–c2 and c1–c6 aids in visualizing the groups that are gauche to the y group on c1.  click this link and watch some academic videos that may you more understand the topic