C.
Number of half-unit cubes = 18
V = 2 1/4 cubic units
volume of rectangle: length * width * height
[tex]\hookrightarrow 1\dfrac{1}{2} * 1\dfrac{1}{2} *1[/tex]
[tex]\hookrightarrow \dfrac{3}{2} * \dfrac{3}{2} *1[/tex]
[tex]\hookrightarrow \dfrac{9}{4}[/tex]
[tex]\hookrightarrow 2\dfrac{1}{4}[/tex]
To find number of half units cubes:
volume * 8 half-unit in every cube
[tex]\rightarrow 2\dfrac{1}{4} *8[/tex]
[tex]\rightarrow \sf 18[/tex]
