He needs 20 more unit cubes to completely fill the prism
<h3>How to determine the number of unit cubes?</h3>
The dimension of the prism is given as;
4 by 3 by 3
The volume is calculated as:
Volume = 4 * 3 * 3
Volume = 36
He has already filled 16 units.
So, the units remaining is
Remaining = 36 - 16
Evaluate
Remaining = 20
Hence, he needs 20 more unit cubes to completely fill the prism
Read more about volumes at:
brainly.com/question/1972490
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