As the shock waves travel in concentric outward circles from the epicenter, and the diameter is measured 120 miles,
area of a circle =<span>π</span><span>r*r</span>
d=120
<span>r=<span>120/2</span></span><span>r=60</span><span><span>60*60</span>=3600</span><span>3600*π=11309.734</span>
<span>11309.734 square miles</span>
It can be described as a constant variation
As oil ,coal ,gas ,solar ,wind and water power
