Slope is used for which of the following situations?

slope is used to determine if lines are parallel.
slope is used to determine if lines intersect.
slope is used to see if points are collinear.
slope is used to find the equation of a line

The table below shows the approximate masses of a dust particle and a grain of pollen. dust particle 0.000000778 g grain of pollen 0.00000000155 g the mass of a dust particle can be estimated and written in the form a × 10^b, where a = 8 and b = the mass of a grain of pollen can be estimated and written in the form a × 10^b, where a = 2 and b = based on the estimates, the mass of a dust particle is approximately blank times larger than the mass of a grain of pollen.