A school is overcrowded a continuing to use moklular classmoms. The school can be expansed, or a new schooil can the buit is "split the load" between the schoods. User benefits come from improvemems in school performasce for the expanded or new schools. If a new school is built, there are more benefits becmuse more students will be able to walk to school, the average distance for those who ride the schood buses will be shorter. and the schools will be smaller and more "student friendly." The disbenefits for ite expanded school are due to the implet of the consiruction process during the school year. The interest rate is $8\%,$ and the life of each altemative is $20$ years. Which alternative should be chowen? What is the incremental ratio for the preferred alternative?

$\backslash$table$[[,$ Alternative,Expand,New School$],[$User benefits $($$M$/$yr$),2\mathrm{.}1,3\mathrm{.}1],[$User disbenefits $($ $$M),0\mathrm{.}8,0],[$First cost $($ $$M),8\mathrm{.}8,10\mathrm{.}4],[$Operations and mainte$-,0\mathrm{.}95,1\mathrm{.}7],[$nance $($$M$/$yr$),,]]$