$17\mathrm{.}3.$ Figure $17\mathrm{.}9$ shows the relation between corm yield and nitrogen fertilizer application. With respect to corn grown on "Plainfield loamy sand," estimate the yields for four cases: $(1)$ no fertilizer applied, $(2)100$ kg N applied, $(3)170$ kg $($current usage$)$ applied, and $(4)200$ kg applied. Given that com is $1\mathrm{.}3\%$ nitrogen by weight, calculate the percent of applied nitrogen contained in the harvested com for the latter three cases. Are we reaching the point of diminishing returns with respect to nitrogen application? Where does the residual nitrogen go$?$

Problems $17\mathrm{.}4$ and $17\mathrm{.}5$ refer to the following table:

Grams of Corn and Bean Protein Required to Give Daily Requirements of Essential Amino Acids

$\backslash$table$[[$Essential Amino Acids,Corn,Beans$],[$Tryptophan$,,],[$Lysine$,70\mathrm{.}0,47\mathrm{.}9],[$Threonine$,72\mathrm{.}2,33\mathrm{.}0],[$Leucine$,37\mathrm{.}5,44\mathrm{.}3],[$Isoleucine$,27\mathrm{.}4,44\mathrm{.}8],[$Valine$,49\mathrm{.}0,39\mathrm{.}3],[$Phenylalanine$,38\mathrm{.}8,44\mathrm{.}9],[$Methionine$,35\mathrm{.}0,39\mathrm{.}3]]$