a)

$1{\mathrm{cm}}^2=100{\mathrm{mm}}^2$, zatem:

$8{\mathrm{cm}}^2=8\cdot 1{\mathrm{cm}}^2=8\cdot 100{\mathrm{mm}}^2=\underline{800{\mathrm{mm}}^2}$

$12{\mathrm{cm}}^2=12\cdot 1{\mathrm{cm}}^2=12\cdot 100{\mathrm{mm}}^2=\underline{1200{\mathrm{mm}}^2}$

$1{\text{dm}}^2=10000{\mathrm{mm}}^2$, zatem:

$4{\text{dm}}^2=4\cdot 1{\text{dm}}^2=4\cdot 10000{\mathrm{mm}}^2=\underline{40000{\mathrm{mm}}^2}$

$1{\text{m}}^2=1000000{\mathrm{mm}}^2$, zatem:

$23{\text{m}}^2=23\cdot 1{\text{m}}^2=23\cdot 1000000{\mathrm{mm}}^2=\underline{23000000{\mathrm{mm}}^2}$

Uwaga!!!

W książce w ostatniej wielkości w tym podpunkcie pojawił się błąd. Powinno być $23{\text{m}}^2$, a nie $23\text{m},$ jeśli chcemy zamienić na ${\mathrm{mm}}^2$.

---

b)

$1{\text{dm}}^2=100{\mathrm{cm}}^2$, zatem:

$5{\text{dm}}^2=5\cdot 1{\text{dm}}^2=5\cdot 100{\mathrm{cm}}^2=\underline{500{\mathrm{cm}}^2}$

$34{\text{dm}}^2=34\cdot 1{\text{dm}}^2=34\cdot 100{\mathrm{cm}}^2=\underline{3400{\mathrm{cm}}^2}$

$1{\text{m}}^2=10000{\mathrm{cm}}^2$, zatem:

$9{\text{m}}^2=9\cdot 1{\text{m}}^2=9\cdot 10000{\mathrm{cm}}^2=\underline{90000{\mathrm{cm}}^2}$

$16{\text{m}}^2=16\cdot 1{\text{m}}^2=16\cdot 10000{\mathrm{cm}}^2=\underline{160000{\mathrm{cm}}^2}$

$1{\mathrm{cm}}^2=100{\mathrm{mm}}^2$, zatem:

$200{\mathrm{mm}}^2=2\cdot 100{\mathrm{mm}}^2=2\cdot 1{\mathrm{cm}}^2=\underline{2{\mathrm{cm}}^2}$

---

c)

$1{\text{m}}^2=100{\text{dm}}^2$, zatem:

$3{\text{m}}^2=3\cdot 1{\text{m}}^2=3\cdot 100{\text{dm}}^2=\underline{300{\text{dm}}^2}$

$27{\text{m}}^2=27\cdot 1{\text{m}}^2=27\cdot 100{\text{dm}}^2=\underline{2700{\text{dm}}^2}$

$1{\text{dm}}^2=100{\mathrm{cm}}^2$, zatem:

$400{\mathrm{cm}}^2=4\cdot 100{\mathrm{cm}}^2=4\cdot 1{\text{dm}}^2=\underline{4{\text{dm}}^2}$

$50000{\mathrm{cm}}^2=500\cdot 100{\mathrm{cm}}^2=500\cdot 1{\text{dm}}^2=\underline{500{\text{dm}}^2}$

---

d)

$1{\mathrm{km}}^2=1000000{\text{m}}^2$, zatem:

$7{\mathrm{km}}^2=7\cdot 1{\mathrm{km}}^2=7\cdot 1000000{\text{m}}^2=\underline{7000000{\text{m}}^2}$

$58{\mathrm{km}}^2=58\cdot 1{\mathrm{km}}^2=58\cdot 1000000{\text{m}}^2=\underline{58000000{\text{m}}^2}$

$1{\text{m}}^2=10000{\mathrm{cm}}^2$, zatem:

$60000{\mathrm{cm}}^2=6\cdot 10000{\mathrm{cm}}^2=6\cdot 1{\text{m}}^2=\underline{6{\text{m}}^2}$

$1{\text{m}}^2=100{\text{dm}}^2$, zatem:

$500{\text{dm}}^2=5\cdot 100{\text{dm}}^2=5\cdot 1{\text{m}}^2=\underline{5{\text{m}}^2}$