Answer:
21. Vol. = L ^ 3
or, 27000 = L ^ 3
or, cube root undefr 27000 = L
Therefore, Edge length = 30 cm
22.
a. v = l ^ 3
or, 64000 = l ^ 3
or, cube root under 64000 = L
or, l = 40 cm
Also,
surface area = 6 a ^ 2
= 6 * 40 ^ 2
= 6 * 1600
= 9600 cm ^ 2 #
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