A)
Answer: V = 348cm^3
Explanation: Volume = Base * Height * Length
So if you substitute with the given values you get:
V = 16cm * 2.9cm * 7.5cm
B)
Answer: D = 0.57g/cm^3
Explanation: Density = Mass / Volume
so if you substitute with the volume you calculated and the given mass you get:
D = 200g / 348cm^3