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.
Visible light, ultraviolet rays, and X-rays are all parts of the  electromagnetic spectrum, and travel at the same speed. Humans can  see visible light, but not ultraviolet â¦ rays or X-rays. Ultraviolet  rays have shorter wavelengths, higher frequencies, and higher  energy than visible light. X-rays have shorter wavelengths, higher  frequencies, and higher energy than ultraviolet rays.   This means that ultra violet and x-rays can do far more damage to  our flesh than light can.