[tex] \qquad\qquad\huge\underline{{\sf Answer}}{} [/tex]
Surface area of a cube is :
[tex]\qquad \tt \dashrightarrow \:6 {a}^{2} [/tex]
where, a represents side length of each edge.
[tex]\qquad \tt \dashrightarrow \:a = 6(6.4) {}^{2} [/tex]
[tex]\qquad \tt \dashrightarrow \:a = 6(40.96)[/tex]
[tex]\qquad \tt \dashrightarrow \:a = 245.76 \: \: unit {}^{2} [/tex]
it can be taken as an approximate of :
[tex]\qquad \tt \dashrightarrow \:a \approx245.8 \: \: unit {}^{2} [/tex]
