plz help ASAP with explanation

[tex]\displaystyle\bf \boxed{V=abh \ ; \ 1dm^3=1litre=1000cm^3} \\\\a=12cm \ ; \ b=8 cm ;\: h_1=7 \; ; \ h_0=h_1+h_2=?\\\\abh_2=1,2litre=1,2dm^3\ = 1200cm^3\\\\ 8\cdot 12 h_2=1200\\\\h_2=12.5 cm\: then \\\\h_0= 7+12,5=19,5 \\\\Answer : the \ height \ of \ the \ tank \ is \ 19,5 cm[/tex]
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Explanation:
The volume of a rectangular block is V = L*W*H. So we multiply the length L, width W and H.
For the smaller rectangular block, up to the water level shown, we have a volume of V = L*W*H = 12*8*7 = 672 cubic cm
Since 1000 cm^3 represents 1 liter, this means the tank has 672/1000 = 0.672 liters of water already.
Add on another 1.2 liters of water to get to 1.2+0.672 = 1.872
Therefore, the full tank's capacity is 1.872 liters
This converts to 1.872*1000 = 1872 cm^3
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The largest rectangular block has volume 1872 cm^3
We know the length and width (along the bottom) is L = 12 and W = 8 respectively. The height is unknown, but we can solve for it like so
V = L*W*H
L*W*H = V
12*8*H = 1872
96H = 1872
H = 1872/96
H = 19.5
The height of the tank is 19.5 cm