A. 17.6
The slope of a line is defined by the equation:
[tex]m=\frac{y_2-y_1}{x_2-x_1}[/tex]
where
[tex](x_1,y_1)[/tex] are the coordinates of the 1st point
[tex](x_2,y_2)[/tex] are the coordinates of the 2nd point
Here we are told to calculate the slope using the yellow dots. The coordinates of the yellow dots are (approximately):
[tex](x_1,y_1)=(3.8,3)\\(x_2,y_2)=(6.3,47)[/tex]
So, by applying the equation, the slope of the line is:
[tex]m=\frac{47-3}{6.3-3.8}=17.6[/tex]
B. The density of the substance
In the graph represented, we have:
- Plotted on the x-axis: the volume (in mL) of a substance
- Plotted on the y-axis: the mass (in grams) of the substance
This is a straight line, so the slope is constant at every point: this means that the slope of the line is basically equal to the ratio
[tex]\frac{m}{V}[/tex]
where
m is the mass
V is the volume
This quantity, however, is just the density. In fact, density is defined as the ratio between mass and volume of a substance:
[tex]\rho = \frac{m}{V}[/tex]
And therefore, the slope is just the density (measured in g/mL).
