Answer:
F = 47.6 N
Explanation:
- Newton's 2nd law can be expressed as the rate of change of the total momentum, respect of time, as follows:

- So, in order to find the average force exerted by the skater on the wall, we can find the change in momentum due to the force exerted by the wall (which is equal and opposite to the one exerted by the skater), and divide it by the time interval , as follows:

⇒ Fsk = 47.6 N (normal to the wall)
Answer:
D. gravitational potential energy
Explanation:
In 2011 NASA researchers identified features on Mars known as Recuring Slope Lineae ( or RSL ). RSL are relatively dark and narrow features.They are thought to be a signs of salty liquid water on Mars. One hypothesis for RSL formation is that they form when underground bodies of salty water leak into the surface.
Answer: Recuring Slope Lineae.