Question 354519
square base 30 cm by 30 cm
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let the height be h cm
volume of tank = 30*30*h
= 900h cu.cm
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volume of water in tank = 20% of 900h cu.cm
= 180h cm^3
five times 180h  will fill the tank.
full tank = 900h cm^3
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1000 cm^3 = 1 liter
36 L = 36000 cm^3
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900h =36000 
h=36000/900
h=40 cm