Considering the plot of total mass (y-axis) versus volume (x-axis), which of the following is true? a. the plot should be rather linear because the slope measures the density of a liquid. b. the plot should be curved upward because the slope measures the density of a liquid. c. the plot should be curved upward because the mass of the liquid is higher in successive trials. d. the plot should be linear because the mass of the beaker stays constant. e. none of the above.