In a right triangle, which of the following ratios represents the cosine of angle $\theta$?

Given a right triangle where the side adjacent to angle $\theta$ is $4$ units and the hypotenuse is $5$ units, what is the value of $\sec \theta$?

In a right triangle, which pair of angles are $\mathrm{linear}\mathrm{pairs}$?

Which of the following statements is true about the tangent function $\tan$ in a right triangle?

In a right triangle, if angle 1 is a right angle so $m\angle 1=90°$, what is the measure of angle 2 if the third angle is $45°$?

Triangle $ABC$ is a right triangle with angles $A$, $B$, and $C$. If angle $C$ is the right angle, which statement is true about the measures of angles $A$ and $B$?

Triangle xyz is isosceles. Angle y measures $a$ degrees. What expression represents the measure of angle x?

$\text{If two parallel lines are cut by a transversal, then the pairs of alternate interior angles are:}$

In the context of right triangles, how do rays $ab$ and $ac$ relate to the formation of an angle at vertex $a$?