problem $4\mathrm{.}11$

Determine the CBOD, NBOD, and total BOD of a $100m\frac{g}{\text{I}}$ solution of analine $(C_3{H}_{7}N{O}_2)$

CBOD $=107\mathrm{.}865,$ NBOD $=71\mathrm{.}91,$ Total BOD $=179\mathrm{.}775$ mg$/$l

problem $4\mathrm{.}21$

Consider example $4\mathrm{.}11.$ Use a spreadsheet to develop a Streeter$-$Phelps DO sag curve and determine the characteristics.

i need problem $4\mathrm{.}21$