How do you figure the probability of an event occurring?

What point is the projection of q on a) r b) s c) t

Write the point-slope form of the line passing through (2, -12) and parallel to y=3x.

Find the volume of the solid obtained by rotating the region enclosed by the curves y=1x and y=7^-x about the x-axis. (use symbolic notation and fractions where needed.) volume =