$\backslash$table$[[$DATA$],[$Customer$,$X coordinate,Y coordinate,Demand$],[1,10,55,40],[2,50,100,65],[3,70,25,5],[4,95,25,30],[5,95,80,30]]$

You want to build a plant to serve your customers above and you are interested in different alternatives.

a$)$ Using the grid below, show the customers' locations and draw the vertical and horizontal lines to calculate the net pull amounts.

b$)$ Calculate the slope of each region and show it on your grid.

c$)$ Starting from the point $(70,80)$ and moving in south$-$west direction, draw the isocost contour lines to find the alternative locations for your plant.

d$)$ Select two different coordinates $($alternatives$)$ that lie on your contour lines and show that the TOTAL COST of these are equal to each other. Report your cost calculation if the cost per unit distance per unit demand is $30TL.$

a $h$&$r$