What cause sudden upper back pain after sleeping

How do the uv rays cause damage?   what exactly causes the skin to burn;   can you be more specific about this mechanism?   3. how do photosensitive medications increase a person's sensitivity to sunlight and therefore increase their risk of getting burned?     what kind of medications can increase photo-sensitivity, can you think of some examples?

One hospital ceo insists on including performance data in the hospital’s annual report. “we do very well on most measures, except for one or two, but we put those in anyway,” she says. “we want to hold ourselves accountable.” does this practice demonstrate effective or ineffective leadership?

Viral infections in plants ) can be controlled with antibioticsb) can spread within a plant via plasmodesmata c) have little effect on plant growthd) are not spread by animals