Marcus measured the masses and volumes of samples of four different substances, and he calculated their densities. the table shows marcus’s measured and calculated values. substance mass (g) volume (cm3) density (g/cm3) aluminum 5.7 2.1 2.7 copper 14.4 1.6 9.0 iron 9.5 1.2 7.9 titanium 8.6 1.8 4.8 next, marcus obtained another sample, which is made of one of the four substances that he had already measured. the table shows marcus’s measured values for this unknown sample. substance mass (g) volume (cm3) ? 9.5 2.1 what is the unknown sample made of?