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.
95% of the UV energy hitting the earthâs surface is UV-A. The other 5% is UV-B. In fact, almost all of UV-B radiation is absorbed by our atmosphere (Ah, the wonders of an ozone layer). UV-A penetrates the skin more deeply than UV-B, however, its UV-B that causes more short term and long term problems. Problems like skin cancer, aging, and DNA damage. Itâs also UV-B waves that are primarily responsible for your sunburned skin. How do these rays cause erythema and the pain that comes with it? UV-B wavelengths donât penetrate very deeply, but they cause photochemical reactions in your epidermis (the outer layer of your skin) and damages DNA.