Regional metamorphism . A. takes place at cool temperatures and low pressure B. takes place at cool temperatures but high pressure C. is another name for thermal metamorphism D. is another name for dynamothermal metamorphism

Dynamothermal metamorphism

Explanation:

Dynamothermal metamorphism takes place under the effects of direct pressure and heat.The heating element promotes the recrystallization and shearing stress not only facilitates recrystallization but is also helpful in deforming the rocks producing newly formed structuresDynamothermal metamorphism can be said as regional in character as it is related geographically and also from its origin to large orogenic belts (An orogenic belt involves a series of geological processes collectively called orogenesis in which a continental plate shrinks and is pushed upwards to form one or more mountain ranges)

∴ We can say Regional metamorphism is another name for dynamo thermal metamorphism.

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