Câu 1: 68 km 9m =...............m
Câu 2:9km 68m=...............m
Câu 3:19m 8cm=....................cm
Câu 4:5$k{m}^2$ 175${\mathrm{m}}^2$=............${\mathrm{m}}^2$
Câu 5:4${\mathrm{km}}^2$45${\mathrm{m}}^2$=.................${\mathrm{m}}^2$
Câu 6:7${\mathrm{km}}^2$ 8${\mathrm{m}}^2$=.....................${\mathrm{m}}^2$
Câu 7:15${\mathrm{m}}^2$ 9${\mathrm{cm}}^2$=....................${\mathrm{cm}}^2$
Câu 8:4${\mathrm{cm}}^2$ 6${\mathrm{mm}}^2$=..................${\mathrm{mm}}^2$