Ultraviolet rays from the sun are dangerous because they can damage skin. Why do ultraviolet rays cause damage?

Asatellite component is in the shape of a cube with 10cm edges, has an evenly distributed mass of 2 kg and one bolt hole at each of four corners. if the maximum predicted random vibration environment is 10 grms, what bolt size would be a good choice for restraint? what other factors might drive bolt size besides force/stress?

What is the weight of a 8-kg substance in n, kn, kg·m/s2, kgf, lbm·ft/s2, and lbf?

Which form of cell division creates the sperm and egg, resulting in half of the chromosomes as the other cells?