Why might your ears pop when you travel up a mountainside or fly in an airplane?

Your ears pop in airplanes because the air high above the surface of Earth is The High pressure when you are going up into the air

The pressure up in the plane or on a mountain is lower than the pressure at ground level. Since the air pressure is lower, that means some of the trapped air in your inner ear must escape to stabilize the pressure (so the pressure in your ear is equal to the lower pressure outside). As a result, your ears 'pop' to let out that trapped air in your ears and ensure that the pressure in your ear is equal to the pressure outside. 

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 

The answer to this qustion is c