B and C.
Step-by-step explanation:
A. A = 1/2bh
[tex]A=\frac{1}{2}*6*4[/tex]
A = 12 m^3
B. A = bh
[tex]A=48*.5[/tex]
A = 24 m^3
C. A = 1/2h(a + b)
[tex]A = \frac{1}{2}*4(9+3)[/tex]
[tex]A=2*12[/tex]
A = 24 m^3
D. A = 1/2bh
[tex]A=\frac{1}{2}*8*3[/tex]
A = 12 m^3
