Answer:
30
Explanation:
To know how many cubes were used to create a resctangular prism you only have to calcute the volume of the rectangular prism, in order to do this you´ll need the next formula:
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Which is base area, multiplied by the height:
5x2= 10 units of base.
The base you multiply it by 3:
10x3=30
The total volume is 30 units, and those are the number of units needed to make the rectangular prism.