Microscopes with life science and physics
Centre of Mass then axis of rotation and then moment of inertia. This was the toughest question for your level... happy to help ^_^. It was purely experimental question.
Geologists do not use a minerals color or streak to identify them because some minerals can have the same streak and color but the correct answer is
b) color
Kinetic Energy = 1/2 * m * v²
1/2 * 30 * 20²
1/2 * 30 * 400
12000/2
6000 J.
