1. In an isosceles triangle $\triangle PQR$, side $\overline{PQ}$ is congruent to side $\overline{PR}$. If the vertex angle $\angle P$ measures $80^\circ$, what is the measure of base angle $\angle Q$ in degrees? ___
2. In $\triangle XYZ$, side $\overline{XY}$ is congruent to side $\overline{XZ}$. If the measure of base angle $\angle Y$ is $70^\circ$, what is the measure of the vertex angle, $\angle X$?
3. Which of the following sets of angle measures can form an isosceles triangle?
4. An isosceles triangle is also a right triangle. One of its angles is $90^\circ$. What is the measure of one of the two equal base angles in degrees? ___
5. According to the Base Angles Theorem, if the angles $\angle B$ and $\angle C$ of $\triangle ABC$ are equal, which statement about the sides must be true?
6. In $\triangle LMN$, the angle measures are $m\angle L = 25^\circ$, $m\angle M = 110^\circ$, and $m\angle N = 45^\circ$. Which is the longest side of the triangle?
7. In $\triangle RST$, $m\angle R = 62^\circ$ and $m\angle S = 48^\circ$. Which option lists the sides in order from shortest to longest?
8. In $\triangle GHI$, the measure of $\angle G$ is $85^\circ$ and the measure of $\angle H$ is $55^\circ$. The shortest side of the triangle is ___.
9. In $\triangle UVW$, $m\angle U = 75^\circ$ and $m\angle V = 30^\circ$. Which statement must be true about the side lengths of $\triangle UVW$?
10. In $\triangle PQR$, $m\angle P = 105^\circ$ and $m\angle Q = 40^\circ$. What is the measure in degrees of the angle opposite the shortest side? The answer is ___.