Answer:
a) up
b) down
Step-by-step explanation:
When the cube is less dense than water, it will tend to float (move upward). When it is more dense, it will sink (move downward).
a) 160.2 kg/m^3 < 1000 kg/m^3. The cube will move up.
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b) 7849 kg/m^3 > 1000 kg/m^3. The cube will move down.