Help me i need asap.

Answer:
290m^3
Step-by-step explanation:
First, split the composite figure into 2 shapes. In this case the easiest would be the top cuboid (I'll call it A) and then the bottom one (B).
A: Vcuboid = lxwxh = 5x3x6 = 90m^3
B: 8x5x5 = 200m^3
Answer = 90+200= 290m^3
(I sometimes doubt myself so apologies if this is not what you're looking for)