This problem is providing the volume and density of a fuel an airplane uses to function, so its mass is required and found to be 208 kg according to the following:
In science, we define density as the degree of compactness of a substance and can be mathematically calculated with:
[tex]d=\frac{m}{V}[/tex]
Thus, since this problem provides us with the volume and density, one can solve for the mass as shown below:
[tex]m=d*V[/tex]
Hence, we plug in the given data and convert liters to milliliters in order to have consistent units:
[tex]m=0.821\frac{g}{mL} *253L*\frac{1000mL}{1L}\\ \\m=207,713g =208 kg[/tex]
Learn more about density: https://brainly.com/question/952755