Answer:
(a) The volume of the woman in liters is 75 L 
(b) The volume of the blue whale in cubic meters is 121 m³
Explanation:
From the question,
Mammals have approximately the same density as fresh water. 
The density of fresh water is 1000 kg/m³, 
∴ The density of mammals is approximately 1000 kg/m³.
Now, we will convert this to kg/L 
1L = 0.001 m³
∴ 1 m³ = 1/0.001 L = 1000L
Hence, 1000 kg/m³ = 1000kg/1000L = 1 kg/L
The density of mammals is 1 kg/L
(a) To find the volume in liters of a 75 kg woman, 
From the formula 
Density = Mass / Volume 
Then, Volume = Mass / Density 
Mass of the woman = 75 kg 
Density = 1 kg/L 
∴ Volume = 75kg / 1kg/L = 75 L 
Hence, the volume of the woman in liters is 75 L 
(b) To find the volume in cubic meters of a 121,165 kg blue whale. 
Using the same formula
Volume = Mass / Density 
Mass = 121165 kg
Density = 1000 kg/m³
∴ Volume = 121165kg / 1000 kg/m³ = 121.165 m³ ≅ 121 m³
Hence, the volume of the blue whale in cubic meters is 121 m³.