a)
[tex]v = \frac{2 \times 2 \times 2}{3} = \frac{8}{3} = 2 \frac{2}{3} [/tex]
b)
[tex]v = \frac{ \frac{2 \times 2}{2} \times 2 }{3} = \frac{2 \times 2}{3} = \frac{4}{3} = 1 \frac{1}{3} [/tex]
c)
[tex]v = \frac{1 \times 2 \times 2}{3} = \frac{4}{3} = 1 \frac{1}{3} [/tex]