Outside the city of Five Points, a small illegal dump is found containing old computer monitors. The concentration of lead in the soil is 200 ppm in a primary area, a circular region with a radius of 7 meters centered at the dump. A secondary area with an additional width of 7 meters has a concentration of 20 ppm.
Lead can be treated at a cost of $9/m^2 with phytoremediation with sunflowers or $45/m^3 with removal of soil by excavation.
Show your work in each calculation below.
a. What is the range of lead concentrations in mg/kg?
b. What is the area of the primary area? What is the area of the secondary area?
c. Evaluate the cost of remediation through phytoremediation and excavation to 1
meter for the primary and secondary area.

like many students at university, you may be unhappy about the results you attain in exams. you may feel that even with all you are doing there must be something more -- or different-- you could be doing to get better grades. we have all at some time or other heard of that student who only studies a couple of hours for final exams and scores a's every time. we stand in awe of those who seem to breeze through without undue effort and seem to need very little in the way of studying to nail an exam. the reasons for success, in what i think are the vast majority of cases, are less esoteric than many students think: successful students consistently apply a series of productive strategies with view to attaining clearly identified learning and grade goals throughout the academic term.