Explain why data from at least three seismic stations are needed to locate an earthquake epicenter

Each station has a circle made of possible epicenters. When you have atleast 3 epicenters you can narrow it down to 1 epicenter and there's that final point. Each station can detect how far away the epicenter was (by transverve body waves). When you only have one seismic station it's impossible to locate an earthquake epicenter.

Explanation:

The question says, "A body that weighs 80 N falls freely and reaches the ground with a speed of 10 m / s: Calculate its kinetic energy, Calculate its gravitational potential energy when it is 2 meters high. "

Weight of a body, W = 80 N

Speed with which it reaches ground, v = 10 m/s

Weight, W = mg

g is acceleration due to gravity and m is mass of the body

Now the kinetic energy of any object is given by :

Potential energy is given by :

We have mg = 80 N and h = 2 m

Hence, this is the required solution.