Angle-Angle Similarity Exploration

Are two triangles with two pairs of congruent angles similar to each other? Drag the sliders to change the angle measures. Toggle the check boxes and determine if the two triangles are similar.
Questions: 1. What must be true about the third angle measures in both these triangles? What theorem gaurantees this is true? 2. When two pairs of corresponding angles are congruent what is true about their corresponding sides? Is this always true? 3. Create two similar triangles with new angle measures. Check the box show sides. Can you determine the scale ratio (scale factor)? 4. Can you use this scale ratio and find the length of CA? Check your work by checking the box "Show CA"