Answer:
A: greater than the volume of object B
Step-by-step explanation:
Based on the dimensions, the volume of object A is ...
(3 cm)(2 cm)(4 cm) = 24 cm³ = 24 mL
If object B displaces 19 mL of water, we presume that is its volume. Since 24 mL is more than 19 mL, we conclude ...
The volume of object A is greater than the volume of object B.
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Comment on density
We have presumed that object B is completely submerged. If it is not, then the relative volumes will depend on the densities. If the density of object B is less than about (19/24) g/mL, its volume may very well be larger than that of object A.