2×9.81 m\sqrt{2} \times 9.81 \mathrm{~m}2×9.81 m
9.812 m\frac{9.81}{\sqrt{2}} \mathrm{~m}29.81 m
9.81 m9.81 \mathrm{~m}9.81 m
2×9.81 m2 \times 9.81 \mathrm{~m}2×9.81 m