You draw 3 circles around the stations with the size of the circle equal to the distance from the earthquake. Then you simply find where the edge circles all overlap.
Answer:
<em>k = 25.18 N/m</em>
Explanation:
<u>Simple Harmonic Oscillator</u>
It consists of a weight attached to one end of a spring being allowed to move forth and back.
If m is the mass of the weight and k is the constant of the spring, the period of the oscillation is given by:

If the period is known, we can find the value of the constant by solving for k:

Substituting the given values m=5 Kg and T=2.8 seconds:

k = 25.18 N/m
If you increase the mass m of the car, the force F will increase, while acceleration a is kept constant. Because F and m are directly proportional.
If you increase the acceleration a of the car, the force F will increase, while mass m is kept constant. Because F and a are directly proportional.
How can Newton's laws be verified experimentally; is by setting this experiment, and changing one variable while keeping the other constant, then observe the change in F.
Hope this helps.
The answer is C) the density of the rock
Density of rock is the dependent variable, because it depends on the temperature. The temperature can’t be the dependent variable because ,the density of a rock does not have magical powers that can change temperature of a room. However changing the temperature of the room ,will change the density of the rock. Hope this helps !