[tex]P = \frac{a \times h}{2} \\ \\ P = \frac{0.8dm \times 16cm}{2} = \frac{0.8dm \times 1.6dm}{2} = \frac{1.28 {dm}^{2} }{2} = 0.64 {dm}^{2} [/tex]
Odp.C