A number of factors can lead companies to close stores. One is mergers and acquisitions activity. As organizations join forces under a single umbrella, locations that once competed for sales can become redundant, leading to store closings.
There are 3 types of ultraviolet (UV) rays: 1  Ultraviolet A rays (UVA) make up most of the sun's natural light. They can penetrate deep into the skin, causing wrinkles and premature aging of the skin.  Ultraviolet B rays (UVB) are the main cause of sunburn. They are nearly 1,000 times stronger than UVA rays.
1 They can damage skin cellsâ DNA directly, and are the main rays that cause sunburns. 2  They are also thought to cause most skin cancers. 3  UVC rays have more energy than the other types of UV rays, but they donât get through our atmosphere and are not in sunlight. 4  They are not normally a cause of skin cancer.