#3: Rotation
Use the rotation tool to transform ABC exactly onto DEF. When finished, you should have a new triangle A'B'C' that lies perfectly on top of DEF.
Hint 1: The 'rotation' tool can be found in the transformations dropdown menu along with other transformations like translations, reflections, and dilations.
Hint 2: You may need to create a point to be the center of rotation. You can do either use the 'point' tool or type in the coordinates (e.g. (5, -2)) into a blank 'Input...' space to do this.
Hint 3: If you miss the mark the first time, you may drag the center of rotation point and the image will adjust automatically -- try this rather than starting over!