What are two ways engineers use their understanding of KE and PE to make their designs better / Safer?

Follows are the solution to this question:

Explanation:

Energy shifts at such a rollercoaster ride many times throughout a ride from possibility to dramatic power. Kinetic energy is the energy the object provides for its movement. The coaster machine is traditionally lifted by a rope from the very first hill. It gains energy stored because as vehicles move up.

OR

we can say that whenever anyone travels through an amusement park ride often recognized as a ring road, energy transfers from the opportunity to kinetic energy, because of the layout of the curves as well as the slope, and it is replicated few more occasions during the ride.

Kinetic energy seems to be used in motion.

Its amusement ride vehicles were usually climbed back by a rope from the very first hill, but as the other vehicles move along that route, they acquire potential power.  

answer;

d. are made mostly of liquid

explanation;

-the general   composition and structure planets includes; they have a thick gas and liquid layer covering a small,solid core. mostly the gases are hydrogen and helium atmosphere and layers of liquid hydrogen. for instance neptune and uranus are examples of the outer planets, they have a core covered by ice and ammonia.

-neptune's atmosphere is hydrogen and helium with a bit of methane so there is no oxygen to breath and the interior is made up of frozen water and ammonia with a rock and iron core. thus, there is no liquid water or solid surface to survive.