In a figure where $D$ and $A$ lie on a horizontal line above, $C$ and $B$ on a horizontal line below, and $AC$ is the transversal, consider: Which is correct?

$\angle DAC$ is measured downward from the upper horizontal to the line of sight, making it an angle of depression, while $\angle ACB$ is measured upward, an angle of elevation; since the horizontals are parallel and $AC$ is a transversal, these alternate angles are equal, so all three statements hold.