Solve the Problem $800 \mathrm{~m}$ Of Fencing $80 \mathrm{~m}$ By $320 \mathrm{~m}$ B) $200 \mathrm{~m}$

Multiple Choice

Solve the problem.
-A farmer has $800 \mathrm{~m}$ of fencing. Find the dimensions of the rectangular field of maximum area that can be enclosed by this amount of fencing.

A) $80 \mathrm{~m}$ by $320 \mathrm{~m}$
B) $200 \mathrm{~m}$ by $600 \mathrm{~m}$
C) $190 \mathrm{~m}$ by $210 \mathrm{~m}$
D) $200 \mathrm{~m}$ by $200 \mathrm{~m}$