A bicycle frame consists of two adjacent triangles. The diagram shows some of the dimensions of the two triangles that make up the frame.
Answer these questions about the bicycle frame ABCD. Justify each of your answers.
1. Find the measures of all the angles in the frame.
2. Copy the figure on a piece of paper.
3. Then find the center of gravity of each triangle. Estimate the center of gravity of the entire frame and show it on your diagram. Explain how you made your estimate.
4. Explain how you could modify the frame to lower its center of gravity in order to provide more stability.