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Center of Gravity Problem

For this problem, you are to cannibalize any available code (such as that discussed in Graphics on the Fly) and write a trio of scripts which will allow up to five masses to be placed on a Cartesian grid and will calculate and show the center of gravity for this system.

1. The HTML Page: centerofgravity.html
   • Ask the user for up to five (x,y) coordinate pairs and a mass at each
   • Accept input in a form
   • Using the Graph! button, send the data (as three one-dimensional arrays; see Passing an Array) to a PHP script called centerofgravity.php
2. The Driver PHP Script: centerofgravity.php
   • Since you cannot return values from the script which creates the graph, you need to do the calculations in this script to report where the center of gravity is
   • Report the coordinates of the center of gravity
   • Call the drawcenterofgravity.php script as the source attribute for an image tag, passing all necessary data, to have the graph created
3. The Graphics PHP Script: drawcenterofgravity.php
   Using all of the information passed to it by centerofgravity.php, create a PNG utilizing different, coordinated, contrastive colors to draw the following.
   • Use the code discussed in Graphics on the Fly to create the axes
   • Draw a circle for each mass, having the area of the circle correspond to the mass, the largest one having a standard diameter such as 100 pixels
   • Draw a small circle of a different sort of color to indicate the location of the center of gravity

To see how this could work, view this possible solution.